I know it's one of those things that tends to change over time, particularly if your account rep changes, but wouldn't simply finding a reseller that doesn't suck be the answer here? Perhaps one that lets you automate quotes and purchases...
Quotes in this case are as trivial as a PDF generator that just inserts the fixed price into a commercial offer template. As it stands, you wouldn't believe how hard it is to pry something like that out of a typical SaaS vendor.
I’ll make sure to have another solution in place before next year’s renewal.
I feel your pain
There are still some crucial obstacles to ensure robustness, but I'd love to get your feedback nonetheless. Could I ask some questions over email? I can't find yours, but I'm at andrew@satchel.com
(And thanks for reminding me that I need to add my email to the site.)