Your experience reminds me to manage the portfolio well (i.e. sell losers) and to be patient. 

My question is: when wholesaling, after finding a great deal, do you need real proof of funds to the get the property under contact or is there a way to get it under contract, find a buyer and complete a double closing/assign the right to sell without actually having the cash for the property? 

Better sell everything and live in an underground bunker. 

Growing means refinancing or selling in order to acquire more assets.

I almost exclusively sell bank foreclosures for a large asset management company, and I also do a lot of marketing for wholesale deals.

She owns and sells tons of STR's there. 

Waivo has a different but similar product they sell directly for STR.

I am perfectly fine holding X amount in real estate.If I do see an opportunity another option is to lock it up and sell one of my existing if I think this property will perform or appreciate significantly more.

I believe this tough-on-crime approach will make Albuquerque safer and a better place to do business in the near and long-term future. 

A 1031 exchange is for selling an investment property then buying another investment property.