Two of them are H&R double action revolvers and the other one says American double action. They are 32 cal. As far as condition they all look to be in ok order. Some do have a little rust and some pitting.
My Dad has one like the one with an octagon barrel (top pic, 2nd post with pics). Its a black powder gun. Using modern ammo could result in catastrophic failure (code for blow up in your face.)
Based on what I've seen while I've collected some of these late 19th century inexpensive pistols, if they are in working order, they can go for anywhere between $100 and $250, depending on condition. I've some ambitious sellers try to go higher (some as high as $400 to $500), but that's entering in proper S&W territory and you'd have to be really lucky to get someone to pay that. The .38 S&W variants seem to go more. I imagine that since these are in .32 S&W (aka .32 S&W Short), I imagine they'll go for under $200 (again, that's if they are in working order).
If they don't work, you might get $50 for them for the parts.
As to shooting them with "modern" ammo, the modern .32 S&W rounds are indeed loaded with smokeless powder, but they are loaded to the same levels as the BP rounds. So unless you are finding some crazy hot loaded rounds, you can fire any of the current production .32 S&W rounds in those guns. Virtually all of these obsolete pistol cartridges are loaded that way, since basically all the guns made to fire that round were made to fire rounds loaded a BP levels (and are typically 60+ years old, some over a century).
.45-70 is a round that can buck that trend, since it's stayed as a modern hunting cartridge, so you have to be careful. .32 S&W on the other hand fell off the self defense bandwagon around 1896 when the .32 S&W Long round was introduced.