Radon testing? All wood eh? Will an axe get through to your equipment? Alarms etc Will it be residential? How many will it be able to sleep? Fire exit's for the residents. Smoke alarms. Work with choirs eh? How many cars can you park? Clients with kids? Stuff for them? (go karts - air rifle range - ciggarette machines, beer etc) Seriously a swing outside and a ping pong / pool table might just get folks out of your hair when you need it.. Make it uncomplicated to clean / hose out.. remember we are talking musicians pre-ocupied with their recordings, not where to put an applecore or candy bar wrapper. Some designs beg tidyness others give the feel 'oh whats the use'! Goe for the "keep it clean" look as opposed to the "homey vibe", cause - it aint their home! Can they cook there to save money on food delivery.. Will Balducci's deliver? It aint your house either, so build in lockable cupboards, and storage to keep pocketable items away from light fingered folks. Make it so if a client turns up with delinquent kids - you dont feel nervous - leaving to drive into town to pick something up you need... Comms Fax Phones Internet (recomend wireless laptop connection) Can a manager or artist make a call and not disturbe the session? (cordless) Cost of calls? Metered? Do Cel phones work out where you are? If you have natural daylight (dont like it myself) watch out for my pet peeve, GLARE. carefully organise window / control window, live area windows so everyone can SEE and not be blinded by the reflections. (Fletcher and I don't have one BTW) Where do YOU want to see the light from YOUR vantage point in the control room - in the morning & at night. Angle the property accordingly.. Oh and if you could organise a pitch black cellar with a coffin and some earth from 'the old country' I might be really comfortable working there.. Make it so ANY freelancer / savey self recording artist could learn his way round in 15 mins... and not need the 'code book'