Goodwill payment after car takes year to be fixed

My 2011 Lotus Evora S has been in the main dealer now for over 11 months to fix a poor running problem. They have misdiagnosed the fault several times and the bill has now grown to £5000. The dealer now...

Are there any sports cars which don't depreciate heavily?

I'm thinking of spoiling myself and spending £40,000 or more on a retirement present. So which sports car would you recommend that will not lose money long-term? Perhaps going for something like a Porsche...