New owner 1999 boxster
 

Just purchased a 1999 boxster base with 72k on it for 7k. Was parked for 4 years but runs good. I know I can expect some maintenance and rebuilding.

Only issues I have now is the check engine light which per the owner was a o2 sensor. Will be putting it on a lift this week. any advise on what to check, upgrade, etc?

one more issue, air con doesn't work, not too worried about this as it is a sunny day car which will have the top down mostly

Change fluids, check tires for wear and age/dry rot if you haven't already done so. You can find a ton of resources about what to look for here by doing a search.
Oh yeah -- post a picture too! (Its almost a requirement ... )

A very good year, IMHO, check the codes to be sure, I thought I had a bad O2 sensor that turned out was a bad evap purge valve. Welcome to the community. Picture is a must

Pull the error codes to determine the issue. Hopefully it's just the O2 sensor but a check engine light can mean a lot of different things.

Good advice is to do a pre-purchase inspection by a shop that knows the model in question and this would have included a pulling any codes.