To be honest, the burden is on the vendor. But...
For my own hobby business, I often make hard choices that make it so I get screwed vs a customer.
I never ever accept money ahead of time.
I foot the bill for everything until all is tested to my standards and completed. I cannot tell you how many people want to send money and get the work done sooner. It isn?t morally responsible.
This is the case for my own cores or customer mail ins.
The expense is 100% on me.
From my point of view, if I cannot afford it, it isn?t something I should be doing.
Recently an engine builder proved that taking money for future projects so you can complete existing projects is NOT a good business model.
In the article, I 100% believe the customer was naive is hell and should have paid more of a role, but the vendor himself needs to be held accountable.
Either way, too many people in this industry are in it for profit vs the love of the craft.