What I would be inclined to do Lozbrewer is keep your Braumeister, in March there is a 50l Robobrew/Grainfather look alike coming on the market with step mash program and pump, get that one or get the 40l version to give to your brother $532 delivered. If you ever wanted to brew a heavier beer the 40l takes 8kg of grain.
2nd hand kegs can be a pain in the ass so try not to buy sight unseen (I got mine delivered) after replacing all the seals and the lids and the posts I should have just brought new to start with which I will be doing going forwards. Also the fact that after many many cleans I can still not get the smell of softdrink syrup out of them
I currently have 4 19L ball lock cornys
Buy decent taps, I have a Perlick 650ss and have just ordered some of the flow controlled intertaps as I thought I would give them a go, Would have preferred the perlicks but the gf said no as I have a wedding to save for :s ($83 vs $120 complete isn't that much difference except to her :s)
Tread tape everything and use good tube, I use 5mm Inner Dia & 8mm Outer Dia from cheeky peak