I'm surprised by his battery question - unless you were expecting/concerned about an RTC card that was installed. XT's don't have CMOS.
Judging by the pink DOS book, and full sized HDD plate - I'm expecting it's a 256Kb model with an ST412 hard drive. Although that's just educated guesswork - can't be sure until you open it. I'd also expect when plugged in, the mains filters will blow, and quite possible that a few tantium caps will need to be removed.
I'm considering it because of it's nice case, but postage could be ouch. Also there is the Compaq Portable Plus (1983) and Compaq Portable II floating about. I see the IBM 5140 actually met reserve ($205ish). Unrelated, but I just got a Sega Master System for two bucks, so I should go play with that