For example, a property built in the 1970s or 1980s of 100 units in size is likely to have an expense ratio (operating expenses divided by total income) of 50% or more.  

Understand the fees involved and calculate the total cost for an entire year of management so you can compare the different managers.

So for a very hypothetical and generic example:Purchase Price: $100K ($20K Down) / Closing Costs + Misc: $5K / Rehab: $10K = Total Cash of $33KIf the property rents at the 1% rule, or $1,000 month and your able to cash flow $200 month, you'd be splitting profits 60/40 let's say with your FIL.

Total investment is $415,000.

For total passiveness: bonds, stocks, etfs, notes, syndicationOwning rentals is not entirely passive.

Kannapolis has a totally revitalized town square, and a massive research park downtown that is establishing themselves as a medical research authority in the region with very low prices to accommodate investment.Waxhaw has some of the best (if not the best) public schools in the Southeast.

Technically this violates the due on sale clause (a clause saying that the total loan amount is due once the owner is switched), but I have never heard of a bank actually taking action on this.

I had a slow start but started ramping up my investing in 2017 and since then have purchased three rental properties for a total of 6 additional doors since that time. 

We figure we will be able to charge $900/month per side ($1800 total) but also do not know the first thing about becoming a landlord or where to find tenants.

I totally agree that older buildings can take more time.