I was quoted about $6k to $10k depending on what what products/packages that included what I was looking for.

Tampons and wipes do not break down, even if the packaging says otherwise.I also recommend amending your lease.

Sellers and sellers agents knowing your agent is the real deal, represents real buyers, has great business systems in place and has done the analysis to justify the offer is the total package of negotiating.  

Your experience with the DSCR loan process sounds frustrating, but it's not entirely uncommon for borrowers to encounter last-minute changes, especially in complex transactions like cash-out refinances. 

The biggest obstacle I'm encountering now is the making up the initial down payment.

And once you've got an approved applicant, then you present them with your lease, which needs to be comprehensive in its protection for you and of your property (mine is 24 pages and counting as I encounter new issues, and it contains fines for certain violations) - check your state laws.

Also, helping find other ways to drive revenue, including add-on packages and more. 

Aloha @Chris Heinmiller - Being a technologist and a real estate investor, this package isn't that great.  

I created some resources like an investor package, neighborhood graded map, and contractor rolodex that I can share with you.

Hiring a designer, even a virtual package, may be a good option for you especially if this is your first property.