I would look for similar items premade on Etsy - might give you a good idea of what it cost all in (incuding materials) Unless you are a known artist, I think it is very difficult to figure out what to charge for this kind of thing. I was just making a tote bag out of scraps for a quilt that I just made. I spent about 3 hours on it last night, 2 this morning, and probably another hour before it's finished. At just $10 an hour, $60 plus materials for a simple fabric tote would be a tough sell for most of the people I associate with.