I found someone selling a BCG from a M&P15 Tactical and was wondering who makes them, how good they are, and estimated value (low round count). Thanks!

Depends on the year.  Early on they were primarily CMT parts then supposed to transition to in house.  Who knows what you have there.  With bcgs so prevalent, I would just pick up a new Toolcraft or Aim unless the M&P is dirt cheap.

MY MP15T from 2007 had a poor stake job to boot.

I read they were LMT BCG but it was in an old thread and Idk how accurate the info was. I asked him when the gun was manufactured. It isn't for my build, I'm buying a bunch of new/takeoff parts off someone this weekend which will be enough to build 2 guns except for uppers, lowers, bcg, and one barrel (one included) and a friend is giving me money to build him a gun. I need the bcg to have it done and the sooner the better but I don't want ripped off but trying to keep it budget friendly for him even though the parts I'm getting are worth more than I'm getting them for and what I'm selling him the gun for, I can get it for $80 but I'm not sure what to do. I also need an upper and lower but I'm thinking of just ordering them since I'm having trouble finding someone selling local and maybe ordering a bcg as well but if this is a good deal I want to take it.

http://www.aimsurplus.com/product.aspx?item=XAIMBCGN3BDG&name=AIM+AR%2fM16+.223%2f5.56+Nitride+9310+MPI+Bolt+Carrier+Group&groupid=723

New, nitrided and free shipping for just 9.95 more.

Receivers will be more of a challenge