I don't think the phrase: "Don't trust cheap/unknown artists" is fully correct.
What goes for fursuit makers and every other business (be it independent or a corporation, run by one or multiple people), it's good to have some sort of a 'resume', if you will.
If you've done a lot of business and have something to show for it, it's easier to trust you than if someone would be just starting off and barely anything (or nothing at all) to show for it.
See, it's not only because there can indeed be scammers or other frauds out there, but even a good-willing and hard-working person who just started might make some errors neither yourself or they know of.
That's part of the learning process and a crucial step in growing to a bigger business.
If you come across someone who has nothing to show for what they have done, I wouldn't advise in buying anything from them. It's not just because they have nothing to show for what they are promoting themselves, but how do you know you'll like what you get if you can't even see what they make?
So it partially comes down to thinking about things logically.
If you come across someone who just started out and has some stuff to show for it, try to see if you can find any reviews on it. Maybe even ask the people who already commissioned them in the past.
Also make sure you set up means to protect yourself, as I'm sure the maker does for themselves as well. This means things like:
Make sure you pay in instalments. Whether you have the money or not isn't the issue. Just don't buy 100% from the bat. Even 50% might be pushing it. At most I'd agree to 30% to cover the costs of materials. Anything higher could lead to devastating financial blows, and if you pay 30% it already shows the maker you're willing to pay a decent amount already.
Once they start making it, be sure to request they send through photographs of the process, sending you WIPs (Work In Progress pictures).
In the end:
While there are certain risks commissioning a lesser-known fursuit maker, often they do it to gain experience. Not only will you provide for them an income and a huge compliment by commissioning them, but you'll be giving them more business and experience.
I think it would be better to commission a lesser-known artist than a more famous one. I can speak from experience, but you do indeed need to make sure you protect yourself in that aspect, financially and in other regards.