I have not used Mid Valley for spaying. They are competent for the vet services i have used them for. I would talk SNPLA, they are a nonprofit who specializes in spaying and neutering.
They are reasonable. I'm pretty sure they'll give you an estimate, if not the exact price.
The cost of fixing a dog in heat changes in price dramatically. It's not always a wise thing to do. But if you call I know they will quote you a price.
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