Homemade bass traps are super easy to make, trip to Ikea to buy a couple cheap as chips shelfs:
http://www.ikea.com/us/en/catalog/products/93690707/
Seriously, use these.. you can't even buy the wood alone for the same price for making frame yourself.
Buy a couple packs of Rockwool terrain bats which is the most dense.
A knife (To cut bats to size), a large hole drill (Drill large holes in the back of bookshelfs)
Old bedsheets for front cover.
1 hour later you have yourself some excellent bass traps.
Buy some wheels for your traps, make 3 of above and you can wheel them around and make a vocal booth when needed.
Expensive studio monitors in an untreated room is money down the drain.