In short, I can afford the additional $1100/mo cost of a second house, even until I rent it out.I have around $35K in HYSA and emergency funds that I could use for a down payment, but that's less than 20% which would be required for a conventional loan, assuming full purchase price.

A car forum that I'm a part of, and I know the owner of the forum, told me that the dedicated app required constant work and updates as phones and operating systems changed. 

I think the height requirements in Chicago are 7'6" and we're right on the edge of that. 

Rental should be $1,600 a month.This year, I plan to build one more rental property, and it will require financing.

I don't know what they are but unless there's something in the city that requires that kind of notice, it sounds excessive to me.

My focus is on providing either turnkey-style space for those interested in temporary, infrequent use or long-term leasing for business folks who require conference room space (or perhaps event space).

In Oregon for instance unless your doing a PUD open space cannot be required and you MUST create lots to specified zoning density.. in other words if your zoned 5k sq ft lots U cant ask for 7500 sq ft lots you must be within 10% of the base zoning.

One thing to consider since you are a California resident investing is the compliance requirements for LLCs incorporated in California or operating as a foreign entity here - the rules here are different than most states.  

Passive investments require a lot less work to maintain although they do take considerable work on the front end to do appropriate due diligence (at least if you are a conservative investor).

Given the competitive market at the time, every property was receiving multiple offers, and securing a deal required both strategy and speed.