yes, I think you need to factor in if you really just want them gone, or if you want to make up for the time and money used to get them. The latter is going to take a lot of time as well. I had a clean out for my ponies recently (not as many as you though) and I ended pricing them pretty low, just because I wanted to clear out the space and have them sold. But all you can do is try - I would find a price that you are comfortable with and try to sell for that. If no one bites, you can always lower your price again or put them on ebay.