@benmarte yours has been the most useful response yet, but there is still a large margin here I am trying to close.
I am asking for market area because I understand that rural vs urban areas often have different practices. I am looking for patient volumes to understand what kind of a stress-load can be put on the system and provider for maximum quality/efficiency ratio, documentation time to further understand THAT number. I have a whole expanded set of questions depending on the responses I get to the billing portion, the amount one pays for billing services could really become a factor when making an educated decision on an EMR purchase.
In order to meet Promoting Interoperability you have to have a portal for patients. Are practices hosting their portal in the same virtual machine as their clinical EMR? What are users paying for support on the tool?
Hosting costs are great, I am assuming based on the cited AWS cost there is no need for a separate data server for secure information? (Scanned images, etc)
I am not yet convinced (though I would very much like to be) that practices are prospering in all of these accounts (billing, support, efficiency) on $15 a month.