Eee. Good luck. Like stated before me, most people don't even mount for $150.
Cheapest prices I've seen are by people who are amatures just starting out and they are just in it to grab at money and do sloppy work, you get what you pay for. They usually start at $250 though for a small animal like a fox. Even then it's a gamble because you could get a beetle ridden pelt with holes drilled all in it, shoddy sewing and paste work,etc.
If you happen to have a deviantart account I do know two people who are soft mount artists that don't charge a lot, but still do great work. I think they start at about $300 though.
As for getting a really "high quality" trophy soft mount piece, like things from LittleMissDoeEyes, FoxyCreations and Leopardpaws on deviantart, you'd have to shell out $400 and up.
I got my whitemark mounted from LP, she does amazing work but I had to fork over $450 for him, and that was from his second owner. (I think he sold for $550 originally.)
Still, the best thing you can do is just look around for life sized pelts, cased skinned since most "plush artists" don't deal with other cuts (one I know will deal with any but most people prefer to have them cased)
If you need any help feel free to PM me.

(also I like rigid and soft mounts, I prefer soft mounts since I don't have space to have a bunch of rigids right now. however like you said there are those who hate the idea of soft mounts and will look down upon you for liking them,etc.)