If you're building one at a time and one of the big monster production builders needs work done from your #1 go to, you need a backup plan, and a backup plan to that backup plan.#3. 

I have partnered with a number of production builders that are starting to do what you mentioned.  

of thousands of dollars in lost productivity, so the business is likely a lot less price-concerned than other residents. 

I was quoted about $6k to $10k depending on what what products/packages that included what I was looking for.

Also, someone with real estate investing experience can probably help you shop for loan products that could be more flexible on the owner occupancy requirements so that you can scale at whatever pace you want. 

The best wholesaler and the ones who run it like a business, usually start as productive home buyers.

Home was flipped and I buy the product they sold.

The area among several others is more than capable - the finish product is far more important once you’ve picked an area that’s proven to perform.I’ve bought 25+ for me and clients in the last 18 months and manage 15+.  

Biggerpockets recently came out with a book on real estate strategy.You may want to give it a read.State with Strategy by Dave Meyer - https://store.biggerpockets.com/products/start-with-strategy

There is a product called “transactional funding” for this purpose.