Find a house in decent shape and focus on the areas that will increase the value and appeal to people simultaneously. 

In some cases i have seen rental prices going up after floods as many units are not livable or need repairs so if you end up with a property that was not damaged, you might see some short term higher demand and price increase.

Long term tenants can be a major pain when it comes to increasing the income on a property when renovation is necessary.

I own a PM company and a considerable amount of rentals (some I manage & some I don't & some out of state), land, vacation rentals, etc.

You'll increase in speed as you get better managing your properties, setting rent rates, finding deals and learning the systems. 

We have increased rents on about 8 units now by over $200/mo each by turning 1 and 2 bedrooms into 3 bedrooms.

Because of the prohibited transaction rules, doing so could be a violation of the rules, or at the very least, would limit your flexibility with the investment and increase the chances of a prohibited transaction occurring after the investment is made.Here are some alternatives to commingling the assets: using the Solo participant loan feature to do the deal outside of retirement funds using non-recourse financing from a lender or private source in combination with retirement funds as the down paymentusing a 401k or IRA and partnering with non-disqualified persons

.- Yes, there is increased liability; however, if you take earning your license seriously, it doesn't take much to understand what must be disclosed, how to disclose it, etc.

I have a self-directed 401K (solo 401k), and purchasing real estate for buy and hold.However, I would like to grow it by taking after tax dollars (W2) and issuing myself a promissory note of 50K but instead of doing “minimum” payments of prime + 1%, could I artificially increase it to say prime + 5%?

Because of the prohibited transaction rules, doing so could be a violation of the rules, or at the very least, would limit your flexibility with the investment and increase the chances of a prohibited transaction occurring after the investment is made.