Yes, you are right about the wages.

The area they live in has been invested in by people on either coast who want a return and cashflow (not saying it's wrong to want to make money), but the city has a high homeless rate and low wages.

If it’s kept in-house, what are the current hourly wages?

I don't think it's appropriate for high income earners.

What about wages? 

Eventually, nobody can afford to live in a 3 bed, 2 bath rambler as their wages aren't allowing it to pay for the difference in purchase price. 

I've been paying him $10 per hour which is minimum wage in California.

There's an extremely broad based economy, with high wage earners (that can acutally afford the higher rents) .

:@Damian Baynes Rental income is considered passive income and is not subject to social security taxes as opposed to flipping houses or new construction which would both be considered to be active income and would be subject to those taxes.Not sure what you mean by that, SS taxes are collected on wages, you can flip houses and have only capital gains unless you are paying yourself a salary, which you could do the same thing with rentals or not.

Retirement plans are funded either from W-2 wages or self-employment income.