As the others have said, you do not need professional photos--and it IS entirely possible to get good photos even if you do not have any help. I took these with no help:
These horses were brushed but not bathed or clipped--and they look perfectly acceptable as they are. If you are taking conformation photos it is nice if the mane is combed out and slicked down a bit to make sure it is lying neatly (bridle path not necessarily required), and it's good to clip off any "goatee" the horse may have. Even with winter coming on the horse's jaw line can be cleaned up a bit (you do not need to take the hair off close to the skin, just trim it so that it looks a bit neater)
This horse does not have a bridle path trimmed, and he is presentable:
Standing pictures--I have some of those "done it by myself" ones too but don't have them posted anywhere so will have to hunt them up before I can upload them & show them here.
I hope that you won't send your horses off to auction without making some attemt to get better photos.
Do you have ads up on the various saleboards--LB, the American Shetland forum, equine now, horsetopia, horse clicks, etc? I believe that it does take more than just a website to get horses sold--you have to post ads that will make people aware of your website & your horses.
I think this may be a bad time of year to sell--different people have told me that it usually slows down for the winter and then interest picks up again in late winter/early spring--and I also think that it is really a matter of posting the right ad at just the right time, when the right person is looking for just such a horse as you have to offer. You can post ads several times over & get no interest, then you try once more & someone calls & buys right away.
The others are right though--you DO need to have better photos--photos that actually show what the horses look like. Even if someone contacts you now & expresses interest in a horse, they are surely going to ask for more photos so they can see what the horse really looks like--if you can't provide them at that point the person will almost certainly move on & buy elsewhere.