My company provides an all-in-one solution for clients.

There aren’t many residential development companies operating at this level, which reduces competition and risk.

@Kyle Carter My top recommendation is to begin by contacting property management companies in each target area.

REI investing for almost 20 years, owning a wealth management company for 22 years, suffice it to say there has been a lot go data/spreadsheeting/tax analysis/meeting with my team go into this overall decision to sell the entire portfolio at once.  

I encounter this semi often as I broker to buyers and also own a PM company so often have to do the same or similar transition as you are looking for, for my clients. 

My company provides a comprehensive A-to-Z solution tailored to our clients' needs.

Personal loans through the credit card companies can be approved and fund very quickly and my best rate is 7.9% so shop around as some are much higher.

HELOCs are not available because they are residential loans guaranteed by individuals and what you seek is a type of commercial loan or credit line which are available to seasoned companies with proven financial track record.

The companies that market themselves as "garage door companies" (residential) also almost always do commercial stuff as well, such as what you are looking at.

After reading Brandon and Brian's book, The Multifamily Millionaire, Volume II: Create Generational Wealth by Investing in Large Multifamily Real Estate, I'm a bit puzzled as to if the GP's must have real estate experience, or if someone can connect enough professionals/companies on their team to execute successful investments.