Hi, thanks for the tips @Mazz. I have a tiptop audio rack (a kit) that cam with the µZeus power supply and a 1000mA power adapter. But when I expand the rack to more rows, I will remove the Zeus and place a PSU behind the rack with some bus boards.
I came across the DOEPFER A-100DIY1 KIT 1 WITH DOEPFER 15V2.5 AMP TRANSFORMER, which comes with a power adaptor with 2.5A (I dont have to deal with the wall current), 2 x 22socket bus boards, and it also comes with 4 x 84HP rails! btw, the PSU delivers 1.2A, similar to the Doepfer PSU2.
Basically, to get my 2nd and 3rd row, I simply need some rack ears and Im good to go... buy modules