However, I also invested in bitcoin many years ago at $20, and Ethereum a couple years ago at $10 and believe in crypto currencies.

The buyer has rightly requested that the tenant's security deposits be transferred.

@Ben FreimanSo long as the SiMPLE IRA is more than 2 years old, it may be transferred or consolidated with other tax-deferred funds, including in a self-directed format.  

Usually the more doors per apartment building and/or the more money you put down, the more cash flow per door.You could also look into buying businesses (owning them, not running them), good old fashioned stock market investing (not retirement accounts, im talking brokerage accounts so you can actually use the moeny before retirement age) , cryptocurrency investing, or a mixture of all of them. 

We got started with primary properties that we would rent out when we were transferred.

We lived in it for a year while we redid it definitly we were transferred and rented it out. 

Transfer - This is the insurance solution.

As long as the accounting clearly segregates the assets and liabilities of each Series, each Series operates as a standalone entity that can engage in it's own business, enter into contracts, sue and be sued, and even file for bankruptcy without its liabilities transferring to either the parent LLC or the other Series. 

Most of the skills that going into rehabbing will transfer to new construction.

I've taken advantage of some great 0% balance transfer credit card offers, but always worry it trashes my credit score/DTI.