With crazy prices, no-contingency all cash offers, and a serious lack of supply I was ready to chalk it up as a loss and give up on real estate.

Supply MUST far outweigh demand in order for prices to fall. 

With decreased manufacturing supply costs are likely up and holding costs are virtually certain to increase.   

Trying to calculate supply/demand of a market & looking for a reliable resource helping me determine the current number of multifamily units in a particular city? 

As of right now, housing prices have stayed pretty steady in the Southern California market due to the high demand and limited supply available.

Walking through Lowe's or Home Depot and pricing out supplies can be helpful as well.  

I think that the basic principal of supply and demand will prevail both off and on market. 

When the US reopens the demand will come back but all the supply will be gone.

Your strategy may work better in some markets  than others based on the local supply and demand.3) Yes, Private money is another option, and I recommend Matt Faircloth's book, "Raising Private Capitol" as a way to structure your thinking about, and approach to soliciting OPM.

It doesn't have supply at all but some demand.