What is the latest as far as which airlines provide hotels for trainees, and which ones provide single-occupancy hotels and which ones provide hotel but you have to bunk up (unless you pay for the hotel yourself, of course)?

Eagle/Envoy it's airline provided double occupancy for the first week or two, then single occupancy for the rest of training - both new hire and all future training events.

Mesa provides single occupancy from day 1

Mesa - single occupancy for new hires
SkyWest - double occupancy for new hires
Republic - double-occupancy for new hires

All of the above provide hotel. I think Compass is the only regional that requires you to provide for your own housing as a new hire during training, but there might be others.

Horizon provides double occupancy

I hope his job decision isn't based solely on single occupancy vs double occupancy .If it is may the powers be with him lol

What do you mean, exactly?

XJT - CRJ side (ASA) is single.

PSA provides single occupancy hotels, 75 hour monthly guarantee and 24/7 perdiem during training. With monthly guarantee and per diem, I earned close to three grand a month during training.

L-XJT you have bunk buddies