I'm working with a company who owns a small, 19 unit, senior and low income apartment building.

I would just be careful hopping back in now as interest rates and low inventory are making it very difficult if you aren't finding your own off-market options to buy.

I've been reading more about subject to and here's what I've learned:-Good for sellers who are off market-Have low to no equity-Have a mortgage with a low interest rate (less than 5%)-Be absentee or out of state (vacant property, or have a tenant)The buyer would then take over the mortgage payments, and have the seller sign the deed over to the buyer.

If you tell them their credit score is too low (or some other reason) and somehow you obtained information that is inaccurate, then there is the potential to cause a legal problem. 

Are you looking for steady, low-risk passive income now, or are you comfortable taking on more leverage to scale faster?

If you purchase with 20k you will be paying PMI and the returns are too low. 

Set up a contracts account at both Lowes and HD. 

Yes, people see the low price tag on these self-service options (there are a few more being marketed here, not going to put them on blast) and ignore CPA guidance to go with in person option and it is now coming back to haunt them.

A duplex strategy is a low-risk entry, saving on living expenses.

If you want to work with multiple agents, those agents know there's a very low chance of ever earning a dime, so they won't waste their time.Agents do much more than find property.