If you’re planning a weekend break in a European city this autumn, you’re probably spending your evenings hunched over a computer screen, comparing hotels online. Should you blow the budget on a famous five-star or take a chance with a cheap and cheerful pension?

Finding the right place to stay is not an exact science, but nor should it be a lottery. The rules of supply and demand mean that hotel rates tend to fall into distinct bands.

Assuming you have a rough idea of your requirements, you can set your budget accordingly.

Here at The Sunday Times, our team of pointy-headed boffins has hit on the idea of the “sweet spot”. This is the price you ought to pay in any city for a comfortable room with a bit of character in a good neighbourhood. Pay less and you’ll be compromising too much on location or quality; fork out more and the law of diminishing returns kicks in.

For instance, you might find a promising three-star hotel for £150 a night. In the same neighbourhood, there’s a glitzy five-star charging £450. What does the extra £300 buy? Better bathroom fittings, no doubt, chocs on the pillow and 24-hour room service. But do you really need that?

Of course not: you want to spend just enough to get a cracking little hotel, and not a penny more. Here’s our guide to hitting that sweet spot every time.

Unless stated, rates are for a double room, B&B, on a weekend night in November

AMSTERDAM

Sweet spot: £125

On a weekend break in Amsterdam, our needs are modest: we’d like somewhere cosy, comfortable and clean, with a bit of character and within walking distance of museums, parks and cafes.

So, although we love the sumptuous interiors of the Dylan (00 31-20 530 2010, www.dylanamsterdam.com), on Keizersgracht, we don’t fancy £300 a room.

Instead, try the Estherea (020 624 5146, www.estherea.nl), a charming hotel behind a 17th-century facade on Singel, the city’s oldest canal. It quotes £136, room-only, reduced to £132 at Venere.com.

A little further south, near the Van Gogh Museum and the Rijksmuseum, the four-star Bilderberg Hotel Jan Luyken (020 573 0730, www.bilderberghoteljanluyken.com) has doubles for £121, room-only.

For something a little more edgy, the Lloyd Hotel (020 561 3636, www.lloydhotel.com), in the trendy Eastern Docklands, has rooms in five different star categories. The two-stars are good value at £118, room-only, though it’s worth noting that they get booked up well in advance.

An alternative tactic is to bargain-hunt at well-located business hotels. The NH Amsterdam Centre (020 685 1351, www.nh-hotels.com), overlooking Leidseplein and Vondelpark, has large contemporary bedrooms and bargain weekend rates of £119, room-only.

PARIS

Sweet spot: £125

Hotels in Paris run the gamut from grimy hovels all the way up to the palatial George V, where you’ll pay £525 a night. More than in any other European city, space is at a premium. In a cheap room, you may not even have enough room to stow a suitcase.

Below £100, you’re flirting with disaster, but if you’re prepared to hunt around and tolerate a little Parisian quirkiness, you can find small hotels with character in good locations for £125, though breakfast may not be included.

The hotel-review site I-escape.com, which has a reputation for unearthing well-priced wonders, recommends the Hôtel Thérèse (00 33-1 42 96 10 01, www.hoteltherese.com; £122, room-only), a short walk from the Louvre. Also worth a look is the Hôtel Verneuil (01 42 60 82 14, www.hotelverneuil.com), in a 17th-century townhouse near the Musée d’Orsay. It charges £118, room-only.

Susan Herrick Luraschi, who edits Alastair Sawday’s Paris Hotels guide, picks two personal favourites, both of which charge £118, room-only: Le Relais Montmartre (01 70 64 25 25, www.relaismontmartre.fr), on a quiet street in Montmartre; and the Relais Monceau (01 45 22 75 11, www.relais-monceau. com), near Sacré-Coeur.

Luraschi warns against booking a hotel’s cheapest room. “The trick in Paris is to pay for a top-price room at a three-star hotel, rather than a bottom-price one at a four-star. You’ll get more room and often a better view, perhaps with a balcony. It’s better value all round,” she says.

Standards take another leap at about £160. Herbert Ypma, the author of the Hip Hotels guides, recommends the Trocadéro Dokhan’s (01 53 65 66 99, www.sofitel.com). “Sophisticated Paris with a theatrical twist,” he says. Weekend deals start at £159.

In the same price range is the stylish Hôtel Bourg Tibourg (01 42 78 47 39, www.hotelbourgtibourg.com), in the Marais, which charges £153, room-only. Or try the Luxembourg Parc (01 53 10 36 50, www.luxembourg-paris-hotel.com), favoured by visitors to TripAdvisor.co.uk, which has web-only rates of £156.

ROME

Sweet spot: £150

Location is everything in Rome. Book a cheap hotel and you’re likely to find yourself stranded in the area surrounding Termini station – it’s not exactly salubrious, and you’ll spend half your time waiting for buses to get you to the sights.

So it’s worth splashing out a bit to be near the Spanish Steps, Piazza Navona or Campo de’ Fiori. Just remember that you’re paying a premium to be in the right neighbourhood – you’re not buying luxury. Another tip: avoid rooms facing the street, unless you enjoy being woken by cleaners and binmen at the crack of dawn.

Good bets in this price range include the Hotel Due Torri (00 39-06 6880 6956, www.hotelduetorriroma.com), on a quiet street near Piazza Navona, where doubles cost £119-£164, room-only. Near Piazza del Popolo is the Hotel Locarno (06 361 0841, www.hotellocarno.com; from £160), which has art-deco features and a roof garden.

Kate Shepherd, editor of Alastair Sawday’s Italy guide, suggests the Fontana (06 679 1056, www.hotelfontana-trevi.com), a coin’s toss from the Trevi Fountain, where doubles go for £150. The Hotel Portoghesi (06 686 4231, www.hotelportoghesiroma.com), within walking distance of Piazza Navona, has lashings of character and charges £136.

Martin Dunsford, author of The Rough Guide to Rome, likes the Farnese (06 321 2553, www.farnese.hotelinroma.com; from £143), near the Spanish Steps; and the Albergo Santa Chiara (06 687 2979, www.albergosantachiara.com; from £159), near the Pantheon.

Lonely Planet gets more positive feedback about the Residenza Cellini (06 4782 5204, www.residenzacellini.it) than any other hotel or pensione in Rome, even though it has just six rooms, with prices ranging from £104 to £186. “Service is impeccable,” gushes author Duncan Garwood.

STOCKHOLM

Sweet spot: £110

Stockholm is not a cheap city. Taxis are eye-wateringly expensive, and a night on the tiles can send the healthiest of bank accounts spiralling into the red. So it’s a pleasant surprise to find some of the city’s most appealing hotels offering distinctly modest prices.

In the arty Sodermalm district, the Rival (00 46 8-5457 8910, www.rival.se), owned by Abba’s Benny Andersson, offers frills as standard, including Egyptian-cotton sheets and plasma screens. It has an art-deco cinema, a 1940s cocktail bar and a dancefloor, and charges £105 at weekends. Nearby, the Clarion (462 1000, www.clarionstockholm.com) is picking up good reviews for its rooms, which cost £95.

Just outside the city centre, on the waterfront at Nacka Strand, Hotel J (601 3005, www.hotelj.com) is recommended by the Mr & Mrs Smith guidebook. It’s cool and cosy, with pale-oak furniture, open fires, and rooms at £115. For a more conventional downtown base, try the Best Western Mornington Hotel (5073 3000, www.bestwestern.com; weekend rate £105).

BARCELONA

Sweet spot: £160

Because hotels in Barcelona are relatively cheap, it’s worth trading up. Sure, you can find simple hotels near the city centre for about the £100 mark, but if you increase your budget by £50 or £60, you can pick up a mid-range bargain with a little more pizzazz.

As you might expect in one of Europe’s most fashionable, design-obsessed cities, Barcelona has more than its share of cutting-edge contemporary hotels. The Prestige Paseo de Gracia (00 34-97 225 2100, www.prestigepaseodegracia.com) has 45 high-tech rooms with Bang & Olufsen tellies and free WiFi, as well as personal shoppers. Doubles cost £161.

Nearby, the Hotel Jazz (93 552 9696, www.hoteljazz.com) receives consistently good reports for its friendly staff as well as its sleek, modern design. A double costs £168, room-only, reduced to £160 at Lastminute.com.

One of the quirkiest hotels in Barcelona is Casa Camper (93 342 6280, www.casacamper.com), which is owned by the Mallorcan company that makes Camper shoes. Each room has blood-red walls and, across the corridor, a private lounge where you can lie on a hammock and watch television. Prices start at £160.

LONDON

Sweet spot: £145

It’s one of the world’s most expensive cities, with hotel rates to match. But the past few years have seen the emergence of a dual economy in London. Yes, there are plenty of swanky hotels charging £400 a night, but it’s now also possible to find stylish, comfortable cheaper options, among them the Hoxton Hotel (020 7550 1000, www.hoxtonhotels.com), on trendy Great Eastern Street, where we found doubles for a bargain £99. Its highest rate year-round is just £145.

For a more central location, check out the award-winning City Inn Westminster (020 7630 1000, www.cityinn.com/london), near Tate Britain. Its 460 rooms may be aimed at business people, but it caters well for leisure travellers, with weekend rates of £105, including a glass of champagne on arrival and late checkout.

Another hotel bucking the trend for spiralling room rates is Base2Stay (020 7244 2255, www.base2stay.com), in Kensington. It has doubles for £99, room-only, and is a personal favourite of Tom Bell, editor of Alastair Sawday’s guide to London hotels.

Back in the 1990s, London witnessed an explosion of townhouse hotels. Small, intimate and stripped of frills, they offered great-value rooms at about the £100 mark. Prices have risen, however, and some are now charging £250 or even £300.

So, while we’re fans of the Firmdale group of hotels, we’re in no hurry to pay £317 for a night at the Charlotte Street Hotel, in Fitzrovia, or £223 for the Pelham, in South Kensington. Even the normally good-value Malmaison in fashionable Clerkenwell looks top-heavy at £235.

There are exceptions. Montagu Place (020 7467 2777, www.montagu-place.co.uk), in a Marylebone town house, is fairly priced at £149, though breakfast is not included, and The Sumner (020 7723 2244, www.thesumner.com), near Marble Arch, has attractive rooms from £147.

VENICE

Sweet spot: £130

There are two ways to do Venice: either count the pennies or splurge. And if you do the latter, be prepared to splurge big.

That means staying at one of the celebrated palazzo hotels, such as the Danieli (00 39-041 522 6480, www.luxurycollection.com/ danieli), where standard rooms cost £350 a night, even in low season. For that, you won’t get a view of the lagoon, and you’ll pay an extra £35pp per day for breakfast. Don’t grumble – you’re in Venice.

If high prices bring you out in a rash, you’re better off looking not for hotels, but for good family-run pensioni, B&Bs or locande. The stairs may be creaky and the bathrooms in need of an upgrade, but you’ll be compensated with character, charm and personal service.

Jonathan Buckley, author of The Rough Guide to Venice, says: “There are lots of cheap hotels in Venice, but they don’t tend to offer good value. You can pay £130 for a dingy room with a view of an air-conditioning shaft. But for the same money you can find a beautiful locanda or B&B.”

Buckley likes the Palazzo Abadessa (041 241 3784, www.abadessa.com), near Ca’ d’Oro, where weekend prices start at £132; and Locanda Leon Bianco (041 523 3572, www.leonbianco.it), where rooms with canal views can be had for £140. He also recommends Casa de Uscoli (041 241 0669, www.casadeuscoli.com), a B&B near the Accademia that has elegant rooms with views from £129.

One of the best-value hotels near Piazza San Marco is the oriental-themed Novecento (041 241 3765, www. novecento.biz; from £130). In nearby Dorsoduro, try Pensione La Calcina (041 520 6466, www.lacalcina.com), where John Ruskin wrote much of The Stones of Venice. It has 29 rooms, some with canal views, for £129, including breakfast on the terrace overlooking the canal.

Both Mr & Mrs Smith and I-escape.com are fans of Oltre Il Giardino (041 275 0015, www.oltreilgiardino-venezia.com), a restored three-storey villa with a private walled garden in the sestiere of San Polo. Rooms are a steal at £130.

Winter is a great time to be in Venice, but bear in mind that room rates can rise dramatically at peak periods, including carnival (January 25 to February 5 next year).

PRAGUE

Sweet spot: £130

Out of high season, it’s a buyer’s market in Prague. And, as in Barcelona, this is a city where it pays to trade up. The stylish Hotel Josef (00 420-221 700901, www.hoteljosef.com), a member of the Design Hotels group, occupies two houses in the old Jewish quarter. Rooms are a bargain at £130.

Also in the city centre, and hidden away on a backstreet, Hotel Yasmin (234 100100, www.hotel-yasmin.cz) is popular with the EasyJet set. It has bright contemporary rooms for £134.

Sarah Johnstone, author of Lonely Planet’s Europe on a Shoestring guide, points out that Prague also has plenty of decent hotels charging less than £100. “It’s a small city with excellent public transport, making it easy to get around, so, while there are good hotels in the centre, you’re fine staying in neighbourhoods such as Smichov, Vinohrady and Mala Strana,” she says.

Johnstone recommends the Hotel Domus Henrici (220 511369, www.domus-henrici.cz; £86), a “refined classic” in Mala Strana; and the neoclassical Hotel Julian (257 311150, www.julian.cz), in Smichov, which has doubles for just £64.

Also in Smichov, Andel’s Design Hotel (296 889688, www.andelshotel.com) is a bargain at £85. Back in the centre, the newly refurbished Hotel Imperial (246 011600, www.hotel-imperial.cz) has swirling art-nouveau interiors and rooms for £96.

BERLIN

Sweet spot: £100

You’d be forgiven for thinking that the capital of the world’s third-largest economy would be a pricey place to stay. It’s not. This can be explained in part by the fact that Berlin is so spread out – with no real tourist centre, each hotel is competing with the next.

One of the best areas to head for is Mitte, which straddles the old East-West divide and is home to the Reichstag and the Brandenburg Gate, as well as trendy shops and restaurants. Hotel standards are high, with contemporary styling the norm.

The Sofitel Berlin Gendarmenmarkt (00 49-30 203750, www.sofitel.com), near Potsdamer Platz, combines cool design with high-end comfort, yet has weekend rates of £115, room-only, reduced to £109 at Expedia.co.uk.

Nearby, the four-star Arcotel Velvet (30 278 7530, cc.arcotel.at/velvet.htm) is a little more self-consciously hip, but nonetheless gets consistently good reviews. It has rooms for £91, discounted to £80 at Hotels.co.uk.

Another option is Lux 11 (30 936 2800, www.lux11.com), which offers designer self-catering apartments. Maid service is provided only every three days, but the rates are low – from £86, with a supplementary charge of £11 if you stay for fewer than three nights.