[Retroman1969]

Welcome and congrats on the car!
On both of mine, the interior and dash lights go off shortly after locking the car, but stay on a little longer if I just close the doors without locking them. However, if any interior lights are staying on constantly with the key out and the doors closed there is definitely an issue somewhere. (hopefully the more experienced on here can give ideas of what the issue might be)

Also, check the date on the battery. On the Boxster I bought recently, the date code showed the battery to be 4.5 years old. I went ahead and replaced it with a new one before pressing th car into daily service just to be safe.