From my research it seems prices have gone up a lot in recent years so I am wondering if this strategy is still a feasible option for someone looking to start with a SFH for 150k or below, adding value with a rehab and getting a high enough appraisal to make it work. 

It's just too risky to have that much high cost debt at one time.

While private money isn't highly regulated at the federal level, there are subtle nuances to be aware of in each state that may trigger your loan becoming a security and then the SEC would have regulations to consider.

We would have liked to invest locally but prices here in California were too high for our budget.

There’s a short but informative book written by @Dave Foster as well as some YouTube videos.

I see with this with a lot of local banks or credit unions.The Banker should have walked you through the basics on County loan limts versus Jumbo &  High balance.

You can find a company that doesn't have a high spend/volume requirement and flexible pricing options based on your needs.

I see this trend increasing given SFH in immediate Bay Area won't be built or will be high priced.

Its much better for them to sell a high dollar house to a retail buyer.

This is why I scratch my head when everyone is so high on seller financing.