Diagnostics/Electronic Workshop Manuals, anyone?

[Toaster Pilot]

Any of you use diagnostic software or electronic workshop manuals at home? I currently struggle with a crappy old laptop that's a bit too big and crap.

Hoping to have a garage/workshop space soon so I was thinking about buying a big old desktop cheap and bolting it to a metal computer desk so it can be wheeled around - spend < £50 and have a system that will comfortably run all of the software/stuff I need to comfortably tinker.

Anyone got a better but still poverty stricken solution?

[Toaster Pilot]

is that on Android only?

I've managed to get a (free) PC and a £10 monitor to use for a lot of stuff for now, just need a cheap/free computer desk too!