Quoted from dung:Look at sharpshooter I or II. Not high numbers and equally not high prices. Rare != desirable. It needs a hook of some sort. There has to be a story to it, great art, a game that was well ahead of its time but doomed. For most this is an unheard of prototype that never made it past the cutting room floor. Saying gameplan are next in line for love is just you talking it up. If they are due for love it doesn't matter. What matters is where they are today, not where they might be in two years.
If it was working and had decent sounds/music/code, I would guess $5-6k to a handful of people that have really large collections and chase rarity.
Non-working, $3-4k. As no one seems to have played one, there is no guarantee that it has any music/sounds/code at all even when working.