As for getting rodents online most people will tell you rodentpro.com they have good service and prices. Baby boas should eat every 10 days and every 2 weeks when bigger

belly heat is always preferred if available, but lamps will work fine too.

They will be happy with the same set up that BPs use. Something i notice with mine is he does appreciate a fake plant in there to climb but thats not necessary. 2 hides of course, and a water bowl, but adult boas usually dont need a hide

i have my boa in a sterilite 41 quart tub which is only like 6inches high, i have had him in a tank 13 inches high before and never really saw him exploring north/south too much hahah

hope this helps, im sure someone more experienced will chime in soon!