I started selling mine after three months. My feeling is now and it was back then (2003), the popular opinion of most other lampworkers at that time:
If the beads are evenly round and turns on the mandrel with no "wobble" and the holes are smooth and/or dimpled in, your beads are ready to sell. It does not matter if they are plain spacers or simple beads rolled in frit, they are sellable. Don't let the "fancy" stuff in the Gallery intimidate you into not selling your work. Many of us started out selling simple designs and some (like me) still do.
Photos: Very important! But don't let that scare you. Here are examples of a very simple set up to get great pictures and get started on selling your beads:
Camera - an inexpensive Nikon Coolpix. Very easy to learn and you can find them almost anywhere.
Photo editing - the best one I found is Photoshop Elements and it's worth every penny. My version is really old - version 2. Here is a super editing tutorial if you want to take pictures on a white background, and this automatically corrects any color problems:
I love it and my pictures improved dramatically after I learned how to do this! http://www.wetcanvas.com/Articles2/16432/483/
Photo set up: One cheap aluminum shop "clamp" lamp, about $6.99 and you can get them in any Lowe's or Home Depot. In the section where the extension cords are. (Lowe's)
One 100W equivalent "Daylight" compact fluorescent bulb. (23 watts, I think??) The best for natural color in your glass photos and very little "tweaking" will ever be needed in Photoshop Elements. I used to use "GE Reveal" and they are not good because after a couple of months the pictures start getting bad, with a yellow (sepia) cast. Awful and I never used them again when I discovered the very long lasting compact fluorescent.
A white background is perfect to learn with and I use two sheets of all-purpose printer paper (layered for opacity) for my beads. One sheet is too translucent and "grainy" looking.
This is just one way to do things.