I purchased a 97 boxster with 18000 miles on it when it sits for a couple of days there is a slight engine noise for a few seconds and it seems to smoke when starting is this a normal issue or something I should be concerned about?

 

The smoke is normal if it is for only a few seconds. Any horizontal engine will do so. Oil drips past the valves and into the exhaust when left sitting for a period of time, of which it burns off on startup.