Then, in many cases (consult a tax advisor), the gains are wiped out and the cost basis is reset.The Biden administration is proposing to cap this loophole at gains of $500,000 in order to make wealthy investors pay "their fair share".

Once you have multiple rentals you can spread professional services over them and it is much easier to "make money"We have a separate account where we put all of the repair, vacancy, cap-ex, taxes, insurance. 

But an investor is very unlikely to buy up all three, since it's way cheaper to buy a single 10-unit property and pay based on income/Cap Rate.

You'll pay a massively higher rate for a private loan than you would for PMI, and hard money lenders really cap out at 12 months.

Ask them what their Loan Cap rate is, see if that is the issue.  

They probably think they have a great property and want to sell at a super low cap rate.

My question: Is 10% of rent for maintenance, and 5% of rent for Cap Ex a decent approximation for a single family home in a good area, built in the last 20-25 years?

We improved some bad electrical work (a two-pronged system that wasn't grounded) and did some light cosmetic paint as well as added safety features in a few areas.

Has anyone invested in this area recently or over time, (Brookwood, Woodward, Tanyard Creek Park, and a few more I'm interested in) and know what a good cap rate would be in today's market?

There are a few self-contained guides that you can access here: https://www.biggerpockets.com/guidesI really like the alerts feature that can quickly guide you to current topics that may be of interest: http://www.biggerpockets.com/alerts