While I tend to shy away from dealers, it might be a good car so don't write it off just yet. On the open used car market, the car you are looking at is just another really old car that isn't anything special. Few generic people are going to go car shopping with ~ $ 4,000 and pick this over a 8 year old mini van so the market is very limited.

You never know, the car might have been someone's nice retirement car and they have since passed on. The estate might have traded it on something else and the lot is just looking to get out from under it.

Distance makes it more difficult to drive down the road and check it out. I'd call a MB dealer / trusted independent shop and see if they would give it a pre purchase inspection ( at your expense of course ) . The selling dealer may or may not want to do this. Don't be put off if the seller won't do this, the car is selling for almost nothing ( MB or not ) and they might not want to burn time / expense to transport.

If you still want the car and the seller does not want to burn time on someone that might not buy, a last option would be to draw up a contract where you pay a decent deposit and agree on what level of immediate repairs triggers price reduction / contract cancellation. The car then goes to the dealer for a check.

Lastly, don't let "Florida car" lull you into "no rust". Year round salt air is probably worse than salty snow as it dosen't go away for 9 months+.