They approached me with the deal because they couldn't get the math right nor a bank to finance the project the way they had structured it with the seller.

the community property issue is really moot for 1031 as community property is a state legislated designation and 1031 does not speak to that. 

We have been approached by TONS of developers / owners / investors to do shipping container homes.

Personally I approach from all angels mailing them is my last catch all effort. 

As for competition I try not to worry about it because I'm taking another approach including sitting in on probate court hearings (Tentative Rulings) taking notes and marketing myself to attorneys.

My recommendation is next time you are approached by a sales person, explain to them that you have had high pressure sales people in the past and it makes you uncomfortable.

After reading about the requirements for earning this license, I'm still a little confused about the requirement to be sponsored by a licensed designated broker.If I am working alone, not joining a firm, does that mean I need to form a legal entity and then file to endorse myself as the firm's designated broker?

There is a course that I am thinking to enroll in, for earning a designation for residential management.

Designer and GC will be hitting the ground running on a 4 to 6 week flip.

A purely math based approach would tell you to leverage as much as possible.