I am considering getting a slightly more 'grown up' roadster for some time. I have a limited budget of £5000 which seems to flag up quite a few late 90's early 00's cars and was considering the Boxster, the Z4 or the SLK. I am not looking for anything over 2.7 lt for track days - but a fun car for windy roads where I live that wont completely break me to look after on an annual basis. My concerns are possible expensive mechanical problems and re-sell value after a couple of years. Any advice would be much appreciated.