A few of them seem somewhat spammy to me (e.g. people constantly posting about properties they're selling at a discount) and not much helpful advice. 

I am making an offer soon that I hope is similar (near retail at slight discount rate) that is class A unit in a vacation market.  

It's the one-year required management agreement at 10% that can get you (although you can re-up the following year at a discount if you pay the entire year at once).What you definitely need to avoid is leasing through them, should your property become vacant.

Forced Apperception (BRRRR or buying at a discount) is also a hedge against corrections.

You simply get a discount on this purchase, equal to your tax rate.

I prefer to buy my materials because of my discount and because I’m pretty savvy with finding solid deals on things.

The government would tell you that primary homes have a discounted tax rate and to make up for it they have to tax rentals, AKA small businesses.

Consequently you either sell to the least qualified owner occupant imaginable, likely pay 6% seller assist, get crushed through the home inspection process or come to the conclusion going through that process 4 times is not worth the hassle and find an investor to purchase the homes as a package at a discounted price.

Its probably best to proceed with two separate DSCR cash out refinance with one broker who can get you lender discounts.

Then find matches for that product that you are able to buy at a discount.