Sorry to be harsh but this can go downhill in a hurry. 30-45 days can go on with no end in sight.

My experience in real estate has taught me that its much easier to make a neighborhood go downhill than it is to recover one that hit rock bottom.

I expect he is upset that he now lives next to a rental unit and is afraid the property will go downhill .

Anyways, my goal is to initially build a small portfolio of SFR/duplexes for stable, passive income with ambitions to scale more meaningfully over time as the snowball rolls downhill.

Several properties worth of water drain through this property on its way down hill.

Since I'm held to that expectation by my lenders, I need to be congruent with those expectations regarding the bank's asset (my rental properties).Put in layman's terms, "sh*t rolls downhill."

Can anyone give me an advice on what kind of strategy is usually used by rental property investors when having many rental properties using the leverage system and there’s a markets crash or a down hill situation, to still hold positive cash flow with monthly mortgage payments ?

You don't say where they are so you will have to run your own numbers.Some of the risks to just holding them until you later build would be; will the area go downhill and be worth less when you are ready to build.

Builder went belly up, foreclosures, HOA didn't have enough money coming in to keep things nice and it was downhill from there.

I used Bo Evans, their servicing has gone downhill.