As a self-employed 1099 individual, your best route is most likely DSCR.

@Nold R.In addition to the great post from Dave, possibly consider an option where the property is taken out of the LLC sooner rather than later and held as tenants-in-common prior to the sale, possibly setting you up in a position to take your share of the proceeds and individually purchase a replacement property via 1031 exchange. 

Separate LLC per Property: Maximizes liability protection but adds complexity and costs with individual tax filings.3.

My best advice would be to read through the contract carefully (builders usually have their own individual contract that's written for them and is leaning heavily in their favor).

and connecting with local REI individuals and attending meetups to learn from experienced investors. 

My contractor has one credit card for all of my individually owned buildings (jointly not multiple cards) and one credit card for the building I own in a partnership.

Break down your rehab into individual jobs, for example get a electrician for electrical work, a plumber to repipe the house, a dry wall guy to close out the walls, etc.

Quote from @Austin Schubert: Quote from @Chris Seveney: Quote from @Austin Schubert: Would anyone have a sample template of a proposal that you've used in the past that goes over how your structure a deal with a private money individual? 

Unless you live in area that has many ADUs already built that have been sold with the home or as individual parcels.

Those people overlooking what it means to “materially participate”Here’s the Material Participation Criteria:Spend more than 500 hours on the short-term rental businessDo substantially everything for the STR businessSpend more than 100 hours on the activity and no one other individual spends more time than you doSignificant participation activity for more than 100 hours, and your combined activity in all significant participation activities exceeds 500 hoursParticipating in the business for five of the 10 previous taxable yearsPersonal service activity (non income-producing) for three of the previous taxable yearsRegular, continuous, provable participation in the business for more than 100 hoursA Cautionary Tale: The Story of JacksonLet's take a moment to learn from the mistakes of others.