Totally agree with the comments about technique, damage etc. Be warned!! Coming from bass guitar if you go for your finger ends you can expect them to quickly blister and the ends to drop off. You need to get some meat behind those strings!
For me the upright is just a completely different instrument. If feels different, responds differently and makes you think about what to play in completely different ways to bass guitar.
Gear is a real red herring, the sound is ultimately in your hands far more so that bass guitar and it can be really difficult working out how to get a good stage sound. DB seems to be more vunerable to poor rooms, positioning etc so it's aways worth keeping that in mind.
Slam dunk it's great to try before you commit but in my experience you will need to invest a fair bit of yourself in DB before you can really work out if it's for you. It's also worth considering that it's a difficult bugger to play at first, not helped by the fact that a cheap starter instrument will demand far more from you to make it work. The physical relationship between you and the bass is massive in comparison to DB. A better quality bass will sing better and do more for you however this could run you some serious folding by which time you've probably worked a lot of this out for yourself....
Bottom line whatever your motivation it's well worth a look. DB opens up loads of musical opportunities for you and it's a massively fulfilling instrument once you've aligned yourself with it.
Best of luck