You can deduct expenses like mortgage interest, property taxes, insurance, repairs, and maintenance costs from your rental income.The biggest advantage is depreciation—this allows you to deduct a portion of the property’s value (excluding land) over time, significantly reducing taxable rental income.

If they've owned the property for 15yrs, probably a better chance of owner fatigue than someone only having it for 2 yrs.

.--- Tactic 3: Diversification: He invested across various real estate sectors, reducing risk.2.

Quote from @Melanie Baldridge: It's really simple: increase earnings, reduce expenses, save, invest, and wait. 

Increase earnings, reduce expenses, save up, and buy one property.

Did you buy "points" to reduce the rate margin?

As I'm in talks with the oil company that currently owns the land, what questions should I find out from them that would help reduce any surprises?

So far I have not taken money out of a tithe account when there are losses, but since I give tithe on net profit from all my properties, does it make sense to reduce current year's profits by prior year losses as much as the IRS allows and pay tithe on the net profit?

Just imagine reducing your living expense, owning an asset, and having your tenants pay the bulk of the mortgage, then repeating this a few times over all while every year the rents go up.

These expenses would lower your taxable income and further reduce your overall tax liability.