Adjuster's opinion
First run a CarFax and see what you can find out. Determine from the Seller why there is a Salvage Title on the vehicle. If you are buying the car outright and not placing any lien, check with your Dept of Motor Vehicle dept to see if you can get the title cleaned up etc--some states you can do that. Check with other insurance companies--you should be able to get full coverage but if the vehicle is later totalled out or is a total theft, then the insurance company will diminish the market value by 50%...Thus, if the vehicle is normally worth 30k they will only offer 15k...
If you can find out who owned the vehicle when the vehicle was totalled, that owner should have the insurance paperwork--if it's the present owner, he should provide that info and if it's a prior owner then he should have gotten that info or at least be able to get a copy of the info from the prior owner...
I would not pay more than 13k for the vehicle without more info and only if you can get insurance on it....The seller should already know the difficulty of selling a salvage titled vehicle and should have all paperwork showing why it's worth 20k