I've acquired two cameras of this type (a Thornton Pickard and a Butcher Ensign).
The tricky bit is getting the shutter working. There are different types. One with a single long blind with various fixed apertures in it is fairly straightforward. The type with two separate blinds on two separate roller mechanisms giving a variable gap is much harder.
Golden rule is to use a digital camera (excuse the bad language) and keep snapping pictures and make notes as you dissemble. Amazing how quickly you get to the 'which way around did this bit go again?" phase!
Looking at some on eBay recently, they don't seem to fetch much. Being leather covered they look a bit 'scruffy', usually, unlike the shiny wood and brass versions, which I think means they have little collector appeal - plus they're not really very usable for those who want to take pictures.
I'm lucky enough to have a roll film back which fits mine, so I can take 6 X 6 or 6 X 6" pics.
I'd be interested to see some pictures.