How long does a boxster hold…?

Hello, in conversation with a Porsche specialist a few years ago came the statement that the 911, 3.0 is an indestructible specimen. A vehicle, which produces lower costs than a GTI/GSI etc. in a sporty way, because the technology is robust and designed for motorsports. However, since the Otto normal driver rarely exhausts these possibilities, a 911, 3.0 is always at the lower limit. However, with the newer soft” models this would not necessarily be Now I ask myself the question, a boxster is a robust single-seater model or a “€ grave”. What does the experience look like from the practice, I think of workshop costs engine damage etc. Thank you for your honest opinion and experience.. Greeting and continue to have fun