I suggest doing an internet search on "Horseman LX" and compare photos on the net to yours. In any case what you have is a 4x5 monorail view camera.
The price you can get is likely to be pretty low as the previous poster indicates, as heavy film view cameras are out of favor. To get the maximum price it would help if you can find out the condition of the camera and lenses, such as are there any obvious light leaks via holes in the bellows, any non-obvious ones like pinholes, whether the movements are smooth or not, whether they lock down securely, does the ground glass have any cracks or large scratches, do the lenses have any fungus, scratches, does the shutter of each lens work at all speeds, and are they reasonably accurate etc. If you're not familiar with view cameras you may not be able to figure this out.
You may want to check out the apug.org website as it caters to analog photography and a fair amount of large format photographers hang out there. Some there may be able to offer more advice.
Dan
