I'm the least interested person in art you'll ever know, so how she prices her work I'm not sure. I know she doesn't go by time spent on a piece, but instead how good it turns out. I think she just casually looks at other art for sale that is around the same quality and prices accordingly. After so many rounds of that I think you just get a good intuition for it.

She also has a few art shows she applies to and goes presents at those. I think this is where most of her recurring customers come from honestly, and not Instagram. Though she has had a few commissions from Instagram.

A side note on those looking to buy art, you might refrain from asking for a custom piece. If you see something you like, there's a good chance you don't know why you like it even if you think you do. So when you give the artist a picture you want them to translate into something like oil, it'll probably disappoint. The frustrations I've seen my wife go through trying to get a commission right is tiring.