Bid only as high plus shipping as you feel it its worth to use as a parts rig, and then you will not be regretting what you receive.
Later when you get it, and it is actually running or usable- you can then be comfortable. If it ends up being truly not up to par...
Then you can resell it back on the open market as a parts rig and cash out. Remember: there are closing fees, gate fees, and taxes.
Factor all costs in before arriving at your maximum bid. FYI, run and drive is not to be trusted. The criteria is that it can be jump started and move 10 feet under its own power. If you are going to bid higher because of "Run and Drive" - I highly suggest going and inspecting it before bidding. If you cannot inspect it yourself- revert to my rule at the beginning. I have more than once inspected a vehicle that said "Run & Drive" , found out the trans was slipping, or it had engine knock/etc. Only to watch people bid the vehicle up higher than what they sell for at street or dealer retail. Unwise at best. One time I watched a LX450 get bid way out of control, I bet the high bidder wished he saw what I saw. The previous owner had been dreaming of having lockers and put a factory locker control knob in the dash. But I read on the vin tag it said "K292"... (K294 is lockers) hmmm curious. So I climbed under the rig and looked at the axles... and sure enough- no locker actuators. It was a faker. So in my mind the value was far less, on auction day not only did I get outbid... the vehicle sold for MORE than a K294 locked LX450 sells for on Craigslist. WOW. Be very careful, auctions are not always
the best place to buy. As others have stated, sometimes there are deals- but you have to have a realistic mind. Don't let Pride fool you into overbidding and end up like a gambler in Vegas that loses everything. Set your educated number, if the bid walks away... just feel glad you're not the guy paying for it.