>>52128551
I paid $34 shipped at auction for one in nice condition, got another one with a heavily scuffed outer lid for $25. Both had the 2.4 Ghz processor, 4gb RAM, no HDD, no battery, no power adapter. The $35 one did not have a winblows COA while the $25 came with a barely readable kekdows 7 key.
I would estimate $40-50 for ones in similar condition if you're looking to buy it now.
I added a $30 SSD, $45 new OEM 9-cell, $10 adapter to the $35 one so I'm at $120 right now.
I would recommend a $45 name brand SSD if you're going to put experiment data or anything irreplaceable on it, mine's just a shitpost station so I don't really care. You can save some money if you opt for a HDD or a chinkshit 6-cell instead.
You can probably find fully working, ready to go models for $60-$120, but there will probably be sacrifices i.e. the laptop will probably still have the original slow HDD, practically-killed battery, frayed, temperamental charger as these laptops started shipping in 2008.