NEED HELP WITH VOCAL BOOTH!!

whats up guys im new to this forum and was wondering if someone would be able to tell me whats the smallest size i can go with a vocal booth?? i have an extra bedroom that is fairly small its roughly 11x12 and i need a vocal booth only because i do mostly hip hop/spoken word.i saw that u guys use sketchup and gave it a shot with laying out my room..its horrible probably the worst on here but hopefully u can get the picture..any help is appreciated..thanks :D edit: sorry about that.. the room is 11' 6"x 11x 8ft high, i also have two windows in the room..and my budget is $1000 and under

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