extended warranty

None. They all exist to make a profit - and usually a large one, with administration costs also to be taken into account. One report I read said that the worst only pay out about 10% of premiums in claims. So you'd have to be very unlucky with your car to get back your costs.

A manufacturer's one is likely to be the best value.

If you insist on having one, the RAC/AA do policies - I would imagine they would be the least dishonset of a bad bunch. Best option though is to service it properly. That's the best insurance. There's no reason why, if serviced properly and at the correct intervals and not driven like a race car, that it shouldn't have 150,000 miles of useful life.

None. They generally have such restrictive terms that getting substantial amounts of money (ie more than premiums paid) is highly unlikley. Bank the money that you would service the warranty with in expection of repair bills yourself - that's what these companies do and charge you administration for the service as well.

Several years ago I bought a 12 month old Peugeot 306 TD direct from British Gas Leasing Group. It came with 12 months warranty from

Having the warranty saved me about £500 over 42 months, though the car had to be serviced by a VAT registered garage, so if I hadn't had the warranty and had serviced the car myself the savings would have been negligible. It depends on how reliable the car has been up to now, and whether you intend to service it yourself, or pay someone else to do it.