I know I can easily find a qualifying tenant who will pay $1,000 per month if I don't renew a lease with the existing tenant. 

Common fees will include a set-up fee, a leasing fee for each turnover or a lease renewal fee, marking up maintenance, retaining late fees, and more.

He's seen me grow to four units (3 properties) and I'm thinking, there's gotta be a guide or book that would help him just follow step-by-step how to rent out his existing property and buy a new one.

If lenders reject a HELOC due to lack of W2 income, explore DSCR loans, private lenders, or partnerships to fund new investments while retaining your current property.

It looks like you can use a 203k loan for new construction to reconstruct on an existing foundation.

Those conditions don't exist any more, and the government has the right to regulate land use to try to prevent the current conditions from repeating. 

Usually you're going to have to invest some front-end money to survey it out and work with an engineer to figure out what's possible (generally the more lots the better) based on your existing access to infrastructure, the desirability of the area, zoning rules, etc. 

Requires some pre-planning if the ceiling height exists. 

Is this home in the beach a new construction or an existing home?  

It will co-exist with other "new" payment methods such as google pay, apple pay and credit card etc, because the target customers are different.