There is a strong demand for rentals in these neighborhoods as long as you have a quality product, a good leasing agent, and price your rentals correctly.

Also, as mentioned above, this is a great way to start building relationships with small local credit unions and banks which offer the best loan products for investors. 

If he has only one product in inventory and it’s not selling, then he has no profitable products to offset the loss. 

Hey Zane, I work for a production builder.

The first prototype will have all specified fixtures, finishes and products as My wife and I like and approve.

I’m looking for a list of suggested products (cabinets, flooring, tile, etc) to rehab the interior.

https://store.biggerpockets.com/products/the-house-hacking-s...

The first prototype will have all specified fixtures, finishes and products as My wife and I like and approve.

Like many (most) businesses it requires an investment of capital; money expenditure for ongoing marketing; management of operating, marketing and professional personnel; keeping accounting records and filing tax returns; established sales practices; constant monitoring of goals, budgets, and productivity; establishment and implementation of operational systems; and providing customer service.  

The major reason they fail is usually poor installation.