As a PM, I've dropped the ball on a couple things and my policy is to pay for my mistakes.

OMG, a long list, @Joshua Thompson.Schedules C with zero income and large expenses, particularly interest, taxes, and repairsFlips reported at gross profit instead of full selling price minus cost of goods soldFlips reported as short-term capital transactions on Schedule DSchedules E with zero income and large expensesSchedules E with repairs several times higher than the rentMissing depreciationLosses from rental properties or K1s not showing up on 1040 (not always a mistake, but often is)All expenses grouped into some $40,000 "miscellaneous business expenses"Missing deduction for use of a business vehiclethere are another 20-30 very common errors and oversights, soon to include the missing 20% QBI deduction.

This is about your risk tolerance, no one can tell you the "right" answer but yourself.Putting 20% down on a primary residence is a safe bet.

Once your team is established and you have one or two purchases under your belt, then you may want to start looking at increasing your risk tolerance a bit and looking at gentrifying submarkets within whichever designated city.Also, stay in touch with your agent or wholesaler and stay top of mind.

That is a matter of your risk tolerance and is a good question to ask your lender if you use leverage.

If for instance I have zero debt, and my income could carry 2-3 mortgages; and that still be <50% of my income;  Would there be a problem with me scaling a house every spring for the next 3-5 years purchased as a primary and moved into a LLC?

Second mistake: BOA and Chase bank both had policies they would not give me a re-finance for a mix-use property (I bought in cash).

It would make ZERO financial or business sense for someone to rent a place that small for residential assisted living.Contrary to what others post on here RAL is not a get rich quick scheme and the money is made in operations - you'd have a dumb operator if they paid you much over market for rent - all their costs are elsewhere - namely staffing. 

Put out a policy with my tenants if you break something you pay for it.

On April 16 I was notified that I needed to install hand rails on the front steps or they would cancel the policy.