Are there other legal or financial consequences I should be aware of?

With the future being so uncertain I realized there was a need to do more than just rely on my job for financial security. 

But this one doesn't return investor phone calls or request for financials.

Alternatively if they all love the deal, that's also likely a good sign.You can get a dog of a property in a crap neighborhood that will yield a 13.6% gross cap (not saying yours is), but that certainly doesn't tell the whole financial picture of how the asset will perform.

Build a financial history with your LLC. 

I know that the general guidance is that emergency funds aren't to be invested, but given our financial security and the fact that we already have a personal e-fund in a safe, non-volatile location, would it still be crazy/unwise to invest this 15k in an S&P500 index fund in a brokerage? 

I would like a payoff planner that helps me navigate the various maturity dates and interest rates of my (15 due in 5) mortgages so that I gain the best financial advantage when paying down principal balances. 

It is completely useless to defend any of this with mere opinion when the data says differently.The fact is simply this:Nothing can target motivated sellers, NOTHING can.

There are many scammers out there, with histories (criminal and financial) that they are not proud of, trying to raise money.

I have a renter in there now and am wondering if a cost-seg makes sense to do financially as I am planning to keep the place for 10+ years.