Vocal Room

Hello, i have searched the forum and cannot find something similar to what i am looking for. I am in need of a vocal booth. my situation is bad since we are trying to sell this home and move into our other home. so i want to keep the construction here to a minimum. what i would like to do is build a vocal booth out of 2X6 plates and off set the studs for the soundproofing, and make it modular. I want to build it in sections like, floor, each wall, ceiling... and bolt it together with either rubber gaskets or sealant to close the joints. doing it this way will make it easy to remove when we do sell this place, and possible use it in the studio that will be built in my new homes basement. although that is not a major priority. This booth will be place in a corner with the dimensions of: height 8.0' left wall 7.0' right wall 6.0' my thoughts are to build a floor plate and bolt the walls to it and to each other and then bolt on the ceiling. what i want to get out of this is a place is where someone could go in and record vocals without outside noises interfering the recordings. any suggestions on how this will work and a good layout to do it?

maybe something like this? the entire outside including the top is covered in 5/8" drywall - maybe 2 layers - start with 1... bottom 703 will compress and isolate the booth. think about ventilation. maybe something on the side.