JMHO, but unless you are already very familiar with these cars the very last thing you should be doing is shopping on ebay.
Absolutely, yes, you should get a PPI, but once you've won the auction, it won't much matter, it's a contract, not a maybe, and while you could back out, you'll be out a whole lot of time, money and frustration.
If you must use ebay, find cars that are close enough to go look at and drive them to an indy for a ppi. Still a waste of money, since it's still an auction you might lose, but at least your acting *ahead* of it rather than after.
You are far better off to spend at least six-8 hours reading through threads in the 208 forum and getting some pointed knowledge, and post a couple of meaningful questions, including "how much" you should spend. Then use the net, cars.com is a decent resource, and find good candidates. Don't be afraid to coordinate a long-distance PPI and then go get it if you work a deal. I flew to Denver to get my car (I took a friend who was more familiar with them and we did the PPI then, but I was prepared to fly back without a car) and at that time saved about 20-25% over the local market here. The drive back was fun.
Happy shopping...be patient.