I think Nicole's time estimate may actually be on the conservative side. After all, she's a pro, and perhaps has forgotten how very long it takes to inventory the item, set-up the mannequin, get decent shots (especially when you're working without a permanent photo studio or remotely professional set-up), measure the items (the only part I really dislike), and then upload all the information to your site. That doesn't include the finding, cleaning, repairing, etc. But I love it! I'm glad I'm not relying on it to feed my kids or pay my mortgage, but I really enjoy it and have met so many interesting people in the process -- sellers, buyers, and colleagues.
As for the mannequin -- you can find them at a reasonable price if you look around. Here in Atlanta I managed to find a company that had hangers for cheaper than even the on-line places (I'm a bit OCD and everything has to match, even though I work out of my home). On one of my trips there, I mentioned I needed a mannequin, and the lady said that in the warehouse they had a whole batch of "slightly scratch and dent" mannequins for about $60 each!! Perhaps there's a similar outfit near you? Check the phone book/on line for "store fixtures." I found a reasonably priced dress form on eBay. It's an armless body on a stick, basically, with the advantage that you can pin clothes to it to create the proper fit, rather than having to use clips -- but not useful for anything with sleeves). And check Craigs List because you when a local store closes, they sell all their stuff, including the mannequins, racks, etc!