I only have a single rental (at the moment) and a simple W2 job.

Great way to build a business and a rolodex of listings/sellers.

The guarantee of getting paid and a high hourly rate would be what would entice them to use the hourly rate structure over a commission structure.  

If you're a single mom with student loans, a car payment, and living paycheck-to-paycheck, then $20,000 would be devastating and a reserve is critical.

And as mentioned above, if the lender you are speaking with doesn't know what that is...then you need to go to a different lender.  

Right now the only utility at the garage is power so basically I am starting with a frame and a roof. 

Myself and a friend are looking to get into investing in buying hold single-family homes.

For example we helped a client acquire a $1.5M oceanfront home that is pushing $180-200K per year and a $875k home (with no water feature) generating $125k gross revenue annually

Further, running a very quick and simple valuation based on $900 rents, 8% vacancy, 25% op exp margin, and a 9% cap rate, I'm coming up with an ARV of around $83k, so I'd pass if I were you unless you can get a much lower purchase price.

That makes a real difference.Initially we had one originator, one part-time processor, and a part-time admin assistant.