My experience with selling vehicles on flea-Bay is that the vast
majority of bidders are bottom fishing.  You will seldom get full market
value for a car, though motorcycles tend to do a little better for some
reason (portability?).

The other thing is there is a *lot* of competiton on eBay.  For
instance, there are presently 64 SAAB 9-5's listed on eBay, 12 of them
are 2001's.  This is good for buyers, and bad for sellers unless there
is something very unique about your car or you can afford to sell well
below the going price.

I have had good luck using Craig's List or advertising on SAABnet.com.
These produce only local sales and you make your final deals face to
face so there are fewer misunderstandings.  The downside is no-shows.
You'd be surprised how many people will call, talk to you on the phone,
make an appointment to see the car and then just never show, with no
phone call explaining why.  It's just the way people are these days.
Too many a.sholes.  But CL is free and SAABnet is almost free.

The trick is to make your own private web site with all of the details
and a metric buttload of pictures so callers already have a good idea
what you are hawking.

YMMV