price check for keggles?

i found a 15.5 gallon keggle with 1/2" , 1/4 turn brass valve and 1/2" copper plumbing and a 13.2 gallon sparge keggle with 1/2" , 1/4 turn brass valve and 1/2" copper plumbing on craiglilst. both have tops cut off, used condition.

he wants 150 and 125 for each, i don't know whats a good price to offer, whats a good price for these?

Keg pricing is a very gray area that comes down to your ethical opinion. If you don't mind technically stealing a keg from a brewery you can get a keg for $30-$40 usually. Then it depends on if you can do the mods yourself or not.
Legally buying a keg will run around $100-$150, and that's before any fittings or cutting the tops out.
It really comes down to what is it worth to you to have it already done, did he get them legally, and do you care if he bought them legally.

I personally don't care, got 2 keg's for $40, have another $45 wrapped in 6 welded fittings, an cut the tops off my self. So $85 for two kegs ready to brew with 3 welded fittings each.

Saw someone here selling one with all stainless and a siteglass for $200. You can certainly build it cheaper if you effectively source all of the parts. That seems like a reasonable price when weighing the convenience factor into the mix.