It's not quite the last but it is the last multi species forum. My forum is mainly beardies but we do talk about other reptiles. Check out Australianbeardies.net if you're interested.I ran a busy forum which for years had more traffic than APS currently does, and the cash expenses were very low. The big expense was the time required to manage it. If you're paying for a technical guy to manage that side of things then yeah, it's going to cost a fortune, but if you have someone willing to do that work as a volunteer (which I had) and someone willing and able to manage the site structure, members, moderators, etc (which I did) the only costs are hosting and domain registration (which I paid, I can't remember how much it was but it was little enough that I just paid out of my own pocket and didn't accept or want donations). For a while I put ads up which every month paid multiples of the yearly cost, but I was using the forum as much as anyone and I don't like ads so I took them down. Maybe the economics of forums have changed in the last six years or maybe APS has some different issues I'm not seeing, but it seems to have an active enough community to be viable.
I really wouldn't like to see this forum close; it's the last online Australian herp chat group off Facebook and I think it's valuable to our community.