There was a darn good reason the Russians never did it. It would not last long enough to pay back the original cost. This "moon" will have to have a LOT of thruster fuel, which will raise the cost. Once it runs out of fuel, it will become another junk satellite, and clog up an orbital path. The bigger it is, the more it will cost and the faster it will burn through thruster fuel keeping it stable and pointing in the right direction and in the correct orbit.
Vaporware