The most common portfolio style loan in Texas is a 20 year adjustable rate loan.

It's definitely a common situation for many investors.

If working for themselves, they would gross either 6% if they are on both sides of the transaction or 3% if the buyer comes from another brokerage (most common).Broker other side: if the buyer comes from another brokerage, then they generally agree to split commission (in this case 3% goes to each brokerage).

In Cincinnati, it is common on older 4 families for LL to pay gas, and that can be a very expensive bill. 

It seems common sense that investors wouldn’t want to buy properties in a dangerous neighborhood, etc.

@Ramon Flores I've seen agents work together if they are under the same brokerage, but it's not all that common.

Is this a strategy that is commonly used or is the real estate commission worth the saved time/effort?

I think that’s very common and is a great goal for a lot of newer investors.$200/month can be the start of something much bigger.

There's also common variations in the spelling of the last name.   

I'm encouraging seller-financed noteholders to consider small partials as a way to raise cash. 12 - 24 months on 60+ outstanding payments will result in a minimal discount because, in the most common partial scenario, the buyer is buying near term payments and taking less equity risk.