I haven't seen it stated that you'll have a contract.....is this a verbal agreement, or will there be a written contract? This is CRUCIALLY IMPORTANT. You are potentially looking at a lot of money, so there needs to be NO question about who does what, how much money changes hands, where the scraps go, etc. All of the above is good advice, and as usual, the devil is in the details. My plain belts start at $65. That's for a good piece of leather (9/10oz) sized to the customer's request ( I make it like they want if they don't accept my suggestions....if they're wrong, well they'll pay me to fix it), finished edges, slicked flesh side, dyed and sealed, with a skived and folded tongue, and a belt keeper. From there, it goes up. Lined? Tooled? Conchos? Ranger style? They're all available, but it all costs money. The most expensive one I've made so far was $100, and I think I fairly well gave that one away after I looked at the cost of materials (leather,conchos, and buckle) and time (layout and stitching of raised pieces between the conchos). It's all good though, that one belt has made orders for 3 more....at more appropriate prices.
You are doing the right thing by asking LOTS of questions. I didn't realize how badly I was shorting myself until I had a friend price my products for me. When told me he quoted $100 for the above mentioned belt, my eyes bulged out and my jaw dropped. When he said the customer whipped out the money with quickness, I grinned. I think the most common mistake for those of us getting into this business is that we underestimate the quality of our work and the value that quality has to our customers. It's good to get other people's perspectives.