I bought a horribly converted Mortal Kombat back in the day, I ended up redoing the control panel, new buttons, new cherry switches, new CPO,etc I sold it on ebay for like.... $275, I ended up losing like $100 on the deal but I wanted a dedicated MKII not a bad conversion MK1.
If I ever did sell my MAME cab, I'd just try to at least recover my expenses, I'd be more concerned with the cab going to place where it'd be enjoyed over making a profit. Im actually considering selling my MAME cab so I can MAME my dedicated MKII lol.