Hi everyone here is my tortoise's little mansion (For now until he's huge!!). All parts except for the plexiglass I got at home depot. About $50-60 total cost of construction. Total construction time 1 hour (seriously all i had to do was use #8 1-1/4" woods screws and little 1" finishing nails to piece it together, home depot did all the major cutting, except for the trim of course) My dimensions are 45"x30"x3/4" plywood base board. My walls are 12" high and the "balcony" extends for 12". The supports for the balcony is 6" wide wood boards.
For the Plexiglass its cheaper to just get it done at a local plexiglass fabricator. Cost around $25-30, and its cut to order, no need to worry about cracking the thing, make sure though to use a dremel abrasive tip to make the screw holes for mounting, a regular drill bit will crack the glass. I used 3/8" thickness of the plexiglass, 1/4" would be nicer but about $10 dollars more. ( oh and little 1/2" wood screws to mount it) Also i used a 5/8" half circle trim on all the exposed sides of the wood, just to make it look pretty. I then used a 2x1" board for the frame of the plexiglass.
For the hideaway i just used a old grape container, taped the bottom holes and filled with coir and top soil. Slides right out for easy cleaning and wetting. The heater I used an adjustable heatpad from amazon 17$ 4watt only. Sandwiched it between two pieces of glass. Keeps the hide around 75F. Enjoy and please comment.