Q I have just renewed my Kwik-Fit motor insurance policy and have noticed that if I want to cancel it, the company will charge me £129.50. Given that the full premium is only £620, isn’t this exorbitant? — JH from Glasgow

AThe Association of British Insurers (www.abi.org.uk ) says insurance companies will always charge a fee if you cancel your policy. This is called a short period premium-rate charge.

The amount varies between insurers. The charge comprises a fixed administration levy, along with a pro-rata fee for the period of cover that has elapsed. If you have paid for the policy in advance, these charges are deducted from the refund you are entitled to.

Kwik-Fit (www.kwik-fitinsurance.com ) says its standard cancellation fee is £50 plus a pro-rata charge for the number of months and days of cover that have elapsed. By comparison, Direct Line (www.directline.com) has a fixed charge of a month’s cover, while Co-operative Insurance (www.co-operativeinsurance.co.uk ) has a £35 cancellation fee. Both these companies also deduct a pro-rata charge, calculated on the same basis as Kwik-Fit.

Most insurance companies charge these fees to discourage customers from ending their policy mid-term and taking out cheaper coverage elsewhere. Always read the terms and conditions before signing.

Q I have a 2003 model Ford Ka and am struggling to find a simple list of forward-facing group 1 child seats that will fit. I’m told that the Maxi-Cosi Priori XP is a good buy. Will this fit in my small car? — RK from London

A The Maxi-Cosi website (www.maxi-cosi.com ) has a link to a car-fitting guide for its seats. The company offers several group 1 seats — forward facing and suitable for children weighing 20-40lb — for your Ford. The Priori XP (£145) model will fit into a Ka, as will the Priori SPS (£129) and the PrioriFix (£199) seats. Unfortunately for you, the excellent Tobi seat will not fit your Ka.

Ford recommends and sells the Britax range of seats at its dealerships, starting with the Lord Plus model at £105. This seat is suitable for the Ka. Britax (www.britax.co.uk ) has a simple seat-fitting guide on its website. Every seat in its range is helpfully paired with the individual models of car it can be fitted into. The company makes several group 1 seats suitable for your vehicle.

For more advice, the Child Accident Prevention Trust (www.capt.org.uk ) offers a free fact sheet on child safety in cars.

Q I recently bought a year-old Nissan X-Trail 2.2 dCi from a local Nissan dealership. The fuel consumption is much higher than I expected so I had the car checked by Nissan. I also road-tested it myself and achieved 32mpg in mainly motorway driving. Nissan considers these results to be “acceptable”. The official extra-urban figure for this car is 41.9mpg, with a combined figure of 39.2mpg. I realise that official fuel-consumption figures are not fully accurate, but surely they must give a reasonable indication? — JW from Shepperton, London

A Urban and extra-urban fuel-consumption figures are obtained from laboratory tests over distances of 2.5 and 4.3 miles respectively. The combined figure is an average of the two, weighted to allow for the differing mileages. The main aim is to provide a method of comparing one vehicle with another, rather than to suggest achievable figures on a day-to-day basis.

Several factors affect fuel consumption in the real world. These include driving style, the number of passengers and traffic conditions. Even geography can be a factor — for example, steep hills will hammer your fuel economy.

In truth, to get 32mpg from a vehicle weighing more than 1½ tons with the aerodynamic efficiency of a brick is pretty good going.

Q My wife needs a small car that is economical, reliable and also easily manoeuvrable. We would prefer it to achieve 40mpg in mainly urban driving, and our budget is £4,000. — PS from Cambridge

A The Toyota Yaris 1.4 D-4D GLS has air-conditioning, and a 2002 model on an 02 plate with 40,000 miles is on budget at £4,000. Another good option is the Mazda2: a 1.4D model on an 03 plate with similar mileage will also cost £4,000. You’ll have to pay around £600 more for a TS2 model, which has air-conditioning. Also consider the Honda Jazz. In particular, the 1.4 i-DSI SE, which has air-con as standard. An 02-plate model with average mileage comes in bang on your £4,000 budget.

All three cars are Japanese and have a good reliability record. Being small, with a modest-sized engine, the diesel-powered Toyota and Mazda should manage 40mpg around town. The petrol-engined Jazz should return about 35mpg in mixed motoring, but as there is a new Jazz out soon (see First Drive), older cars could prove a shrewd buy.

Q I have a Golf cabriolet with a fabric top that has been going green since I began parking it in the street. Is there a product that will remove this green stuff and then protect the top from more of the same? — SH from Harrogate, North Yorkshire

A Damp is always a problem for cabriolet hoods and the heavy rain we’ve had this summer won’t have helped matters. Cleaning fabric hoods of this type (as opposed to the vinyl variety) requires a specialist cleaning product such as Turtle Wax Soft Top Roof Cleaner and Conditioner at (£17 from www.halfords.com ).

The package includes 500ml of cleaner plus 500ml of protector. The latter is vital to seal the hood against the elements, otherwise rain would soak in and drench the car’s interior.

Once the top is clean, you can prevent it from going green again by regularly washing the hood with this type of product. If you’re looking for a less time-consuming solution, careful brushing with a soft-bristled brush will also help, but do not use harsh chemicals or a stiffer brush.

Try to avoid leaving the hood down when it is wet, as this encourages mould. If it is left down for long periods, even when dry, this will lead to crease marks that are extremely difficult to remove.

Avoid parking the car near trees as these will drip sticky sap and also attract birds. Finally, do not be tempted to deploy a power-washer on any kind of cabriolet hood since this will damage it.

Q The parking brake of my one-year-old Honda Jazz has been properly adjusted by my main dealer and works fine as a parking brake but it remains useless as an emergency brake. It has very little stopping power and will not lock up the rear wheels if the car is coasting downhill. Is this acceptable? — AF from Aberdeen

A We are not sure why you think of the car’s handbrake as an emergency brake. It is, as the name suggests, simply a brake for securing the vehicle when it is parked.

Years ago, the handbrake used to be thought of as a supplementary brake in case the foot-brake failed. However, for well over 30 years all cars have been fitted with diagonal dual-circuit brakes — two independent systems fitted to opposite wheels; ie, front right connected to rear left. So, for example, should a rock bounce up and split the car’s brake-fluid pipe, you will still retain the ability to control the speed of one front and one rear wheel. As such, the only folks who need to use the handbrake while their vehicle is moving as a matter of course are rally drivers.

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