$500 doesn't sound too bad unless it takes meals off of the table for you.
Once cleaned up, polished up, painted up, they would make a nice little combo for home use, plus you have some tooling which always sweetens the pot a little. You might have worn ways, so while it is just sitting there, see if the compound (the part on top of the saddle that holds the tools) moves back and forth without the handle moving. Shove it in and out by hand. that would be you backlash. See if the saddle will move back and forth by shoving it laft and right, and that shows how much backlash is in that. A little is fine, a little more MAY be able to be adjusted out, and a lot tells you that you need some new parts which may or may not be able to be found. No parts means custom made parts.
The drill press......that is just cool looking, and a small piece of history. Painted and polished would look great. About the only thing that could be wrong with it is the bearing in the quill. Grab the chuck and shove it back and forth and see if there is any slop in it. It would be an easy fix.
NOW......use any slop, the rust, and the dirt floor in the building to your advantage. Some rust is very hard to clean. And rust on the machine like that on the outside, can also be in a motor, although less likely as bad. Tell the guy to plug them in to see if they run. Then start talking the equipment down a little using the rust and so on, and offer him $350. Tell him that everything will have to be dismantled and cleaned properly to be precision like they should be. And tell him you drove 150 miles to take a chance, but the machinery is a little worse in person than what the pics showed. He may hit you back at $450. And like every swinging **** this side of the Mississippi that watches Pawn Stars or your side of the Mississippi....hit him back with $400 and load it up.
Oh....and if you paint things up.....add some color to it. Red, yellow, orange. Something other than gray or green.