Affordability is no more that $4500 per month  morthage/taxes insurance. 

Factor in carrying costs (utilities, taxes, insurance).2.

This is a conventional loan where they also cover your PMI (private mortgage insurance).

Your insurer could recommend one or you can check Google (and, of course, the reviews).

How bad is the insurance, how high are the property taxes, is there an Hoa, etc etc. 

Florida is a unique state for MHP law and the insurance has gotten very expensive there too.I recommend checking out @Frank Rolfe's mobile home university content if you haven't already.

Insurance- need a broker.PM- farm out or you better be good at process management. 

The bay area has many old houses so be aware of what it will take to being them up to code and meet insurance requirements.

I've done plenty of deals without and agent, off market not even on the MLS but I'm one of those wholesalers that did things properly, had qualified buyers before even reaching out to sellers and strictly stuck with assignments.Biggest problem is so many "wholesalers" barely have the understand of a deed or what title insurance is so there's an immense amount of knowledge they need before hand which can just be provided to them by getting a license!

I also have a friend that bought brand new construction, but had to shell out tens of thousands in repairs because the home wasn't built properly, the inspection didn't catch the issues, the builder didn't have a warranty on the property, and insurance didn't cover all the problems.