You don't have to spend a fortune on getting a loft - we bought what used to be a chipmunk house out of the local paper. 15 x 8 and cost us £80, we spent another £50 making it suitable for the doos and then hubbie built the perches himself. All in all we were ready for doos within about a month and cost us about £150 including the lick of paint we gave it. It is big enough for what we wanted.
You dont have to go mad, not yet at least, how do you know that you even like the sport yet? Start simple i say and build up as you go along ;D