I'm thinking they make their money on economies of scale, efficiency and marketing. 

What ways have you found to efficiently track both routine (e.g. replace filters, connect with tenants, check gutters...) and new maintenance requests? 

Look into the efficient market hypothesis.

As it relates to offsite management (3rd party management) we have found that this solution only works if you have a a park that is already stabilized and running at or close to efficiency. 

Connect with deal sources - brokers, owners, and influential third-parties - and build fruitful relationshipsCreate a system to efficiently evaluate every deal you come acrossFind a mentors on BP or in your area that can give you advice along the wayBuild routines and habits help you stay consistent with your prospectingGet a good deal under contract - the money will come, even if you need to flip the contractRelationships are key in this business.

Do you plan to ever exit out of real estate, what is the most efficient way to exit?

I'd go with a conventional unit (96%+ efficiency) unless you're flipping in a B+/A class neighborhood. 

I don’t even think about STR as a strategy here in Boulder anymore, it can still be done but the regulations to comply with (STR license and associated annual fees, taxes, SmartRegs (energy efficiency standards) compliance, must be owner-occupied (even if it’s a duplex you have to occupy the side being rented short term), limits on number of nights it can be rented per year, limits on number of STRs in proximity of each other in a neighborhood, annual inspections, etc.) make it not even worth doing here basically IMO I’d rather just do corporate rentals with 30 day minimum stays or regular term rentals.

They create a tighter building envelope, and allow for a energy efficient home.

With hundreds archived, paging through is not efficient.