No, really...
This fellow put a boat-load of money and seriously modded up his sling - but then put just 2500 miles on it before he decided he had to get every penny back out - and then some. I saw another ad for a 2015 conversion to a 4-seater. That fellow said he put $48,000 into it, less than 8,000 miles, and he would generously take $45 K for his also. That means they were spending between $6 to $18 per mile!
The moral of the story? Mod slowly - be happy!