Using leverage to scale, such as borrowing against this cash for larger down payments?

Maybe start with a part-time ops manager or a reliable lead cleaner to free up your time while keeping quality high.

When do you make owner payments?

If you can come up with an extra 1.5% and finance with a conventional loan you have none of those downsides, a lower monthly payment and PMI only until you hit 20% equity

Section 8 can be a profitable and reliable resource but it is 'their ball, their court' so know the rules first.

If they are, I would pay them off first.I would invest in a different market(likely bigger market) where you can find reliable contractors or find a PM that will be able to manage the properties.

I don't trust them and it so much more reliable to take a few minutes and look at your real competition to set pricing. 

Any recommendations on reliable and top notch cleaners in Raleigh?

If your entity has several years of operating history and good and reliable financials, you may be able to find something. 

In almost all investments, you should have a solid base of reliable, cash-flowing, and hopefully appreciating assets before striking out into something new or riskier.