if you allow the use of it I would mention something in your contract that the tenant is responsible to manage a controlled safe fire or something along those lines.  

The other book you mentioned caters more to that audience and gets people hooked on the idea that they can invest in real estate with no money and then teaches them how in subsequent books. 

So after being laid off a few times in the last 8 years I decided to get back into investing but this time focusing on buy and hold multi family real estate so that I could built wealth that could help me retire my wife who just had a long battle with cancer and survived , but is now back to work, and I want to give her a relaxing life free of all the stress of the world (by the way did I mention she is also in the mortgage lending field) so that explains the urgency to retire her from w-2 work ! 

You mention buying a home or condo.

You'll definitely get the long term appreciation in the San Diego market since our supply levels remain low which helps to insulate our market here, but it will be hard to cash flow on immediately unless you use one of the above strategies I mentioned. 

If he is still doing the same as in the past he would be with the top ones mentioned above.

As others mentioned, a DSCR is worth exploring here.

Advice: Like others mentioned, I would launch as soon as possible despite business of the year. 

Sounds like the Hawaii business that you mentioned is on the island of Oahu.

Plus, as mentioned your risk exposure would be huge if you didn't have a contract in hand to lease, plus they won't want to lease from you, because they are a Sticky or capture tenant.Start small and Make Your Big Mistakes Early.