Whether the seller was open to a buyer commission or not, I wouldn't put an additional cost into any personal purchase.  

Upon BP member recommendations, my husband got his real estate license which now helps increase our access and decrease our transaction costs.

A) it controls my cost.

If any costs go up, developer eats it.

This will cost you money on the back end.

I would guess an older home might be more cost to insure?

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

A good freind of mine set up an STR in a similarly lenient area and found that they could focus much more on guest experience rather than the administrative hassle.

Am I more likely to be able to add $50k or $100k of value above cost in a high Cost RE market or a low cost RE market?  

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.