The link posted by davem is a very good read for anyone thinking of buying an f or Tf
Other than that go for low owner numbers , full history , low millage , recently serviced , long mot and tax , matching tyres all round - all of this will pretty much guarantee a well looked after car ... Miss matched tyres are my pet hate it just stands out to me that there either fitting the cheapest tyre. They can get or worst still .... Part worns which is to methe car has been run on a shoe string and not looked after.
Receipts or proof that the head gasket has been replaced with an updated type and that the water pump and cambelt wee changed at the same time.
Under floor stainless coolant pipes are also worth looking for.
And finally DONT FORGET TO GET A HPI REPORT done before you part with your hard earned cash ....I still cant believe people still take the risk!! My text check costs 3 quid !!