But I agree with most of what Will said as essentials, but what about work surface & space, wouldn't be much fun modding on the floor although if that was my only option I'd probably still do it & buy a few chunky sheets of mdf so I could still use a jigsaw lol .
As you say not having some dedicated work space is a pain, previously I worked on a small kitchen table but I've just moved house and now I have a huge work area..OK so it's on top of the washing machine but it's mine and I don't have to keep packing my work away everyday
The old oscilloscope is a recent acquisition I couldn't resist it for £5 it doesn't work but it would take a mini ITX board



I might be stating the obvious but if you work with MDF the dust is quite nasty stuff so a face mask is advisable when cutting it.