Unless you are a veteran or using a DPA program all loan products require some skin in the game (down payment) and that is how most people start their portfolios. 

I have a mentor in the game that is very successful as a yay or nay resource.

However I would not consider them to be truly passive because they do not put any skin into the game like a good passive investment does (via a sizable coinvestment).

When rental demand dips they suffer with placing tenants or forced to play a game with who can charge the least in the area.  

When it comes to rental properties, cash flow is always the target of the game.

AirBNB isn't the only game in town.You need to be on both at a bare minimum.

Now that I have skin in the game, I'm definitely feeling the policy decisions impact me more so than ever. 

I'd also suspect that as an owner-occupant, one might be able to skirt strict STR laws, and rent out a primary in an extremely in-demand market, especially in the near-term (think collecting huge fees seasonally around CU football games the next few years). 

Focusing on areas that will appreciate well is super important, as equity down the line becomes a huge game changer when growing your portfolio.

We do lots of JV and have found that the best relationships are where everybody has "skin" in the game.