I would not go with the Hobbs time. Don't you wanna get paid for fueling the plane and the walk around and the times when you fly for an hour and then WX forces you down?

Also, then you can go as fast or slow as you want.

I may get a part time gig as a jump pilot. It's $100 a day and you only work from 800-1300. If I were you, I'd get $200 + a day. Especially since there are overnights.