It goes without saying that I understand it's an estimate only and not final numbers until the details are worked out, but it will help me put together a solid financial estimate when doing so.

@Matthew Shultis a big portion of it is the financial ability to survive until you build your business.

What lock should I buy, is Airbnb better than VRBO, etc)The former is probably the realm of good startup basics and financial discipline. 

He or she will tell you exactly how much they can finance based on the current interest rate and the Debt Service Coverage Ratio (DSCR) that they need (typically 1.15).

:).Initial glimpses at the financials show that there are losses for the corporation and the locations that are not yet stabilized.  

The GAP financier was a member here on Bigger Pockets who was just recently paid back his entire balance plus his promised ROI.

I think what you are looking for is someone trained in the ways of real estate investing - an agent that will:Introduce you to FSBO's - Expired Listings and other real estate opportunitiesWill be your fiduciary representativeWill make offers for you on suitable real estateWho understands creative financing; delayed settlement, seller assisted financing, assignment, wholesaling, REO, tenant selection, soft money mortgages, tax salesWho will be responsive to your financial goals and a person of integrity and trustHelp with direct mail and street marketing to locate transactionsHousing and rent court marketingAbsolute aware of financial and contract clauses as well as contract engineeringCan assist in - delayed settlement - automatic extension, performance mortgages, subordination, principal mortgages, options and joint venturesAware of bidding on REO, forclosures, tax sales and public auctionsUp to speed on commercial real estate, lots and land as well as businesses with real estateHow should you treat this wonderful person (if you can find one) -They should have a commitment from in the form of a Fiduciary Buyers Brokers AgreementYour agreement to pay them a commission on any non-listed deals they bring youA bonus agreement for great deals that you closeA gas budget - or a cash payment for gas Kind words and respectTo be sincere and active with the agentRespect from youFirst class training on how to represent youSometimes an equity interest in the great deals the agent has initiatedListings when you are ready to sellYour cooperation - all your financials, tax returns and other information that will help your agent close dealsA few free lunches ----Good luck --- Charles

Given that we are carrying ALL of the financial risk, I am having a hard time seeing why this would be reasonable or fair.

That's a span of time you can't even fathom at your age.2)  BUILD a SOLID FINANCIAL FOUNDATIONGet your credit score to >700 (there's a ton of info on how to build your credit anywhere on BP or Google)Obtain or continue earning W-2 income (this becomes important when you want to obtain a mortgage down the line)Pay down any bad (consumer) debt and don't pile on any additional bad debt.Start saving.

@Matthew CopelandTax Liens and Crowd Funding are pretty much the best options for a smaller account.Most investors will work within the standard financial services space to grow their savings and then switch to a self-directed account once they have the type of funding necessary to participate in more significant non-traditional assets such as real estate and notes.