I am looking for one that:- provides checkbooks, and - pays a decent interest rate.

Providing advice without understanding the full scope of your business and its operational plans could result in inaccurate guidance.As a hard money lender, I provide financing options for both DSCR and fix-and-flip loans.

Sounds like you would still need a conventional loan on top of that to bridge the difference, but it could provide down payment funds. 

Also since equity lines are typically interest only would provide lower carrying costs during planning and construction.

Good call on having a tenant provide intel.

Additionally, consider if additional capital infusion is necessary for the property to achieve desired occupancy levels.

Nor will a title company provide a complete loan package.Your friend needs a lending attorney to prepare a set of loan documents.

Provide them whatever terms, etc the note will be held to.

The competitors all provide washers/dryers, some free and some coin-operated.

This is something I can provide, depending on a few circumstances, shoot me a message, thanks!