If you're considering buying another property in couple of years, cash flow is going to be tough with higher interest rates and higher prices anywhere and in my opinion focusing on cash flow will lead to some bad deals (I can attest to this along with many other California investors who buy in inexpensive out of state markets). 

Some of our clients sell their portfolios in expensive markets like San Diego and reinvest (via 1031 exchange, or in your case it's not necessary) elsewhere.

I would also account for a % increase in expenses per year. 5.

Maybe this is why I have heard on the podcasts that you must be careful investing in inexpensive homes in that 30-40k range.

.- this would impact large brokerage in expensive state like CA for sure.- but i think at the end it would create more and more local brokerage and reducing nationwide brokerage like re/max or exp or compass.

Doesn’t have to be a trailer but that will likely be your most inexpensive option for starting.

How much cash post taxes im bringing in - expenses.

I purchased two houses since they're so inexpensive in the midwest. 

While the issue on hand was resolved we did stack up a good over 9K in expenses. 

There are third-party admin people that can help you set up and administer your solo 401k for a relatively inexpensive fee it's about $300 a year I currently use one company to do the same for my self-directed Roth IRA.I'm looking to go with the 401 option because I can do a 100% contribution up to $20,500 now.that's just a little over my net in one month on my rentals.