Regardless of where your shop is.... in your basement or a busy street corner, by charging out only what you need to sneak by will catch up to you quickly.
Charge him something like $125. per order. If he has enough items in there to reach that is on him. Why should you take the entire brunt of his inability to reach a normal order ??
We just ran a job a week or so ago, where the girl asked for I think it was 50 very small pieces printed, laminated and contourcut. The way it worked out, I said... this will cost you a total of $165. She asked.... why ?? Well, the machines are running continuously, but the amount of media you need, I can get 90 pieces out of it evenly, so you're gonna pay for what I use, regardless of how many you want. So, either pay the $165 for your 50 or get 90 for the same price. Are you gonna need more ?? Yes, eventually. Well, you've just about doubled the size of your order and it didn't cost you anything extra.
So, doesn't the bimbo go and order 100.
I still charged $165 and got the last 10 ganged in with another job.
You've got to educate YOUR customers on how you work and make money, not what they need. Who cares what their needs are, if they inconvenience you or you don't make any real money ??