When we bought our 1998 E300, we were the second owners. The car had Signature Class (Canada) warranty that the original owner had bought when the car was new. It was the seven year (from del. date) warranty to 160K kilometers.
Despite the car having lots of warranty left, we had the car checked VERY carefully prior to purchase. It was only a couple hundred bucks, which to me is cheap insurance.
Many people don't have under warranty used cars checked carefully, thinking the warranty will cover everything. It often won't. Our Subaru Outback is under factory warranty, but I wanted to know how much life was left in things like brakes and other wear and tear items not covered by warranty. The dealer was surprised when we brought it in for a PPI, as it was under warranty. They did a decent job, and it was less than $200.
1998 C230 "Black Betty"