I'm finding the prices on nice condition, WORKING gun games to be going up the last few years. If you want one that looks good and plays good, and is not a dust-covered project, I'd be prepared to pay up to $1200. The $800 game is not gonna be as pretty, or its gonna have mechanical issues. Titles are important too. A working, clean Midway Haunted House, with working sound track, could easily bring $2000 right now from a collector.