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? 

Consider starting with a few lower-cost flips with a smaller loan-to-value ratio to reduce financial strain.Market Research: Sacramento can be volatile, so I’d recommend keeping a pulse on local trends—particularly in the neighborhoods that have potential for growth but haven’t quite hit their peak yet.

Yes of course its price can be more volatile and can go down faster than real estate would but long term it appreciates and pays every month.Curious on BP communities thoughts..

I would be buying into a sellers market in almost any Albertan city.Alberta also worries me as it is known to be super volatile for short periods of time and then sit dormant for up to a decade. 

I've talked to lots of California and a few NYC investors that have lost money (including myself) who bought inexpensive properties in the Midwest mostly and a few in the South (Class C is volatile). - some strategies I've seen California investors use to lessen negative cash flow: house hacking, mid-term rentals (people temporarily displaced from home renovation or insurance reasons like fire), rent by the room, Short Term Rentals. - The ultimate house hack, live in the small ADU unit and rent out the two levels of the main house on AirBnb in San Francisco (I would have thought STRs are oversaturated in S.F. but it worked for them and they stay fully booked).

This can help reduce risk and volatility by preventing overexposure to a single asset class. 1031 is only for investment property.7) Deprecation Schedule resets when the property is purchased in partnership with a DST.

Low Risk: TDAs are insulated from market volatility, offering peace of mind.4.

Quote from @Brandon Croucier: 20% down is terrific on land.It’s a non income producing asset which has increased volatility, typically I see 65 LTV max on land as of late.Thank you Brandon!

I’m predicting that people sitting on the sidelines due to rate volatility over the past year will realize that waiting is futile and will stop sitting on their hands.

The volatility of Austin's RE market also presents challenges.