Buddy, from what I've seen that's just the nature of business. I work for a man that gambles on the future everyday. He buys pallets of tile, rolls upon rolls of carpet and vinyl, and probably has 200 slabs of granite. That's all gambling on what people "may" want to buy, not what he knows they will buy.
Of course we are talking a much much smaller scale here. But we can't take the job without the tools and supplies.
Let's change the focus. Someone wants a non molded western holster for a particular model, say a navy colt. You have the pattern and plenty of veg tan. But he wants it out of Horween, because he read it's the cat's meow. Can you charge him for a whole shoulder plus the holster?
You'll be able to sell some of the left overs on later projects, so why pass the whole cost to him?
Here's a personal example: In my last business I bought out an "existing" company. Being a carpenter, I relied on my predecessors painting knowledge. I had to figure out in short order how to do a premium oil paint finish on new cabinets using an automotive spray rig without any experience. Luckily, Sherman Williams pointed me to an airless rig. That was 900.00. That helped, but we were working in cold conditions with oil based paint.
I fought that finish for weeks before my cabinet component supplyer just nonchalantly asked how was I flashing the oil based paints.
Then he, not my predecessor, explained the process to me.
800.00 dollars later in infrared heaters and after three weeks in lost labor I had a finish good enough to present to my client.
I wasn't able to pass any if those costs onto my client, I just had to eat it.
After that project I switched to 100% acrylics and never looked back. I did several jobs with that spray rig before going out of business.
Maybe that example was too long. But, here I am three years later. I'm no longer in business, but I just used that spray rig (that I haven't touched in a year and a half) to do a 2600.00 job.
Can I get an amen?
This side job paid for Christmas, is helping me send my wife to New York for a teacher's convention, and it allowed me to order a headknife from Knipknives.
I think the 900 bucks was well invested. Oh, and one of those heaters keeps my father in law's shop warm.
Sorry for the late night ramble, I'm going to bed.