I saw that one for sale as well. Looked better in the online photos I guess.
Ours also has only the small tiny little bath vent, I would like to have a normal sized vent fan in the front, above the dinette area. This will be on my longterm to-do list. In the meantime it stays pretty comfortable inside, especially if parked in the shade, but even in a hot parking lot the roof insulation (and likely lack of additional skylights) does a reasonable job of keeping the interior from getting too uncomfortable.
We've posted our camper on Outdoorsy, in case you'd like to check it out for a weekend.