mold...can i fix it myself?

[DJ Cummins]

so we evicted a tenant a few days ago...there is quite a bit of kold, mainly in the bedroom and bathroom. Its very weird and gross. we got a bid yesterday to have it fixed...in doing so, along with cleaning/remediating, they will be tearing out the bottom 4 feet of all the walls. they do not fix the walls, so thats another added cost. my qiestion...can i just go in myself, tear out all of the walls, and put up fresh dry wall and flooring? is that ok? if so, is just throwing that moldy material in a dumpster ok or is there a special procedure? any advice is appreciated. fyi....me ripping out the walls, and having it professionally drywalled is cheaper than the remediation bid alone.