I should have been more clear...I actually have a BLOC with multiple properties securing the interest.

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

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 do have a silent investor, but when it comes to securing funding, it often feels like I’m navigating it alone.

It’s a smart way to dip your toes into investing while securing your first home.You’re not being too ambitious at all!

Loan Security: The property will serve as collateral for the seller-financed loan.

I decided to look into an official duplex or triplex putting 150K down that has value add with renovations and potential unit add but it wont have as much equity because it will be an on market deal. 

.- I will keep their security deposit for funds owed.- I will do my best to garnish future wages until their debt to me is paid in full.This has worked 100% time so far.  

It may feel cumbersome, but their diligence reflects the level of security and service you can expect once onboarded.

Quote from @Keilon Morton: I am looking to secure my first tax sale and need another investor to go in on the deal.