Maybe a mutual drive by each other’s Escondido properties at some point in the near future.  

We saved up extra pays from military deployments, cashed out stocks and mutual funds, When we got a promotion, we set aside the funds over the old salary for a deposit. 

What is a competitive interest rate to offer/ what other levers can I pull to make the offer more beneficial to both parties?

Maxing out your TSP may not be beneficial, depending on your rank, income, and family situation

getting a Real Estate License is not that difficult, and the education you will get will be beneficial,  if you are a hustler you can make a ton of money just selling houses, and if you want to wholesale you can give a seller the option to list if wholesaling wont fit. 

Im also open to collaborate with some like-minded investors if its mutually benefecial.

I think it is beneficial to all parties ( buyer/seller/tenant).

Put it into a trust with the beneficial interest of the trusty being the LLC. 

Call your tenant, get their availability and then work with your mortgage company for a mutually convenient time. 

This was a one-off deal brokered by a mutual friend.