IF your not getting it til August then you have a while for it to smell clean. Have you bleached and disinfected it thoroughly. Use Surgical spirits to clean it and the smell will dissipate if you do it outdoors.

Make sure you have the correct heat and UV for it.

I dont know much about torts but they are veggie eaters so i should imagine most veggies that you would usually buy, beleive they also need calcium dust etc.

Hopefully who ever you are purchasing it form will give you all the info you need

Sorry i cant help much more but i dont know much about torts. Is this one on the Cities list? if so does the owner have paperwork.
I know that some torts have paperwork and sure Hermanns is one of them. IF so make sure the paperwork is upto date. If in any doubt contact DEFRA for more info ( you can find them on google)