I'll try to keep this as short as possible because it's SO MUCH.
I opened for fursuit commissions back in mid February. Client submits in my form, agrees to my TOS and pays in full a few days later. I order the supplies needed (resin bits, silicone, fur, foam, etc.).
Fast forward to March when they're now one of the top three on my list to get started. I let them know and they inform me that they have a new reference sheet since the design changed. Design changes are against my TOS. I save the new file, transfer their information onto it and order some more fabric.
There's been a total of three design changes since then, without a change in reference. As I'm working on this and showing WIP photos I'm being told about things looking "off" from the reference without having them pointed out to me so I'm not sure what I'm doing wrong since there's nothing for me to look at. Looking at their art and commissions (which they appear happy with) there's some variations in the design with each piece.
I'm more than halfway done at this point and they'd like it done in time for Anthrocon but this is really stressing me out between ordering more supplies, them constantly apologizing for the changes (that I'm not aware of) and the fear of finishing it and not having it fit them because they've also changed their measurements a few times. For example, I tell clients to measure their forehead circumference around their glasses if they wear them and that measurement has changed many times between 21" and 24". That's a huge difference! They also tend to type in abbreviations or mix up words/spell words wrong to the point where I'm not sure what they're talking about and that's tripping me up too. I ask for clarification and they get frustrated with me.
At this point should I just refund them and take my loss or finish it since I'm so close and keep biting the bullet while working with them? I'm being as patient as possible and they're incredibly patient too, as well as understanding. I'd feel horrible with going with the latter this late into the process but I've never dealt with a client like this before.