VA loan on a 2-4 unit is a great idea. 

And maybe we have another coming up with Covid if you have some self employed end up with bruised credit because of what's happened I could see this happening again.although we know that appreciation was on fire since 2012 when things hit all time bottoms..Although on devils advocate  lets say the houses never went up . ? 

As you look to scale, just make sure to hold/build reserves for when repairs come up and take your time screening tenants as you will find a vacant unit is much less stressful than dealing with a bad tenant.

Maybe this won’t be a problem if you’ve got just 1 unit but I’ve now got 4 tenants paying $200-$400 multiple times per month and it gets confusing.

As for valuation, I see no reasons why a Junior ADU would negatively impact additional housing unit.

Mainly the "self sufficiency test". 

We have been able to save up some money for our first turnkey multiple unit building.

You could potentially put as little as 3% down if it's a single family home and 5% down for 2-4 units.

@Andrew Steffens the pool of buyers that have six figures of cash (you really need about $150k in cash to buy a $500k STR), have some subject matter expertise, AND want to self manage is even smaller. 

Leverage & Portfolio GrowthInvesting in a solid multi-unit property allows you to leverage your capital into an appreciating asset that generates cash flow.