Hi Graham and welcome
Of course it wont cause offence, that's what we're here for! [

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General opinion is firstly to buy the best car you can (probably stating the obvious!) but with lots of history, that's important. There's still plenty of cars to chose from so don't buy one without. Consensus seems to be to budget £1500 a year which is probably about right as long as you don't have all the big jobs due in one year, i.e. belts, clutch, head gasket. I guess if you're looking at a car with circa 100k miles on it then the belts/rollers should have been done within the last 4 years/40k miles and maybe a clutch too. Some say the water pump should be replaced every time the belts are done but I'm not in that camp.
If you take a look here - http://www.twgporsche.co.uk/servicing/ you can see examples of costs with a specialist. These of course come down if you can do the work yourself. Where in the country are you?
Finally, you have the choice of which 944 to go for.
1. Square dash - the original and feels like a classic car, drives like a go kart
2. 2.7 Lux - not had one of these so can't comment, 16V engines do need revs to keep going but there's a lot of fans of these and plenty about for good money
3. S2 - Very smooth and refined, personally I found it a little dull in the sense it#s deceptively quick, so no complaints on speed! Would make an excellent daily as feels modern, not classic
4. Turbo - my current 944 of choice. Very similar to the S2 but with the kick in the back of the turbo - very nice [8D]
I hope this helps? I'm sure there's someone in your area who can help you, maybe show you their 944. What kind of budget do you have to spend?
Regards
Andy
EDIT: PS: Forgot to say, don't forget to check out the buyers guides on here!