How is DTI calculated for noo investment properties conventional?

[Henry Lazerow]

Curious exactly how does DTI come into play when buying a non owner occupied investment property with conventional mortgages. From my understanding if 75% of rents cashflow over PITI it actually improves you DTI for approval is this correct assuming have 2 years landlord experience? What if you show low income on paper is there still limits, it seems almost as if someone making minimum wage or even no income could buy a million dollar property otherwise as long as it showed a net positive to their DTI? There must be other ratios that come into play to limit investment purchase size to income?