Open market it is 2000 easy sale as-is (just based on parts complete, clean boards, and nice backglass) and more likely 2500.
Good rare games of this era in working order (you would need to shop and rubber it) are 2500 easy.
Friend price of 1500 is more than nice of you.
You can always go hunt Pinside archives to get some ideas of past sales.
This appears to be most recent and it sold for 2350 in 1 day.
https://pinside.com/pinball/forum/topic/for-sale-barracoramn-nice-coosmetics