If you have a good FICO, a decent down payment and closing costs, go ahead an do the first one. 

I get it...I get emotional with properties and buy into the sunk cost fallacy too.

Inherently the steps are the same as if you were purchasing with financing save potentially less closing costs and ability to close sooner (if needed).The terms of your offer (ie -contingencies, closing cost splits etc) will determine what is different. 

Also, what are some other low cost amenities that I can add to my STR that will yield a higher ROI?

A post on recapture.People are concerned about recapture when they cost segregate their improvements and for good reason.Recapture is real, and those deferred taxes will need to be paid.But fear not!

The management company has replied that they don't coordinate with neighbors and just want me to cover the cost of all the repairs. 

I'll save you the details but...Per door cost: $63,300All in Cost: 700kTotal Revenue: 137k(ish) annuallyNOI: 65-73% (in the expenses we included: insurance, taxes, $75/month per door repair expense, management fee 8%, grass cutting, & a misc fund for random crap business license, etc.)Now...

Make sure your rehab is "renter" cost rehab. etc. 

This will cost you money on the back end.

Bonus points if they’re used to working with investors or can help keep costs in check while maintaining quality.Cheers,Kevin I would say this about BRRRRR, especially as a newer investor.