The key to making it work is communication with both tenants and owners - or in my case tenants and me as the property manager.

However they communicate only respond via text or email.

Prompt and efficient communication is essential in this industry.

Your ineptitude may amplify your losses:(You're also jumping to assumptions.We've had out-of-the-county investors that we could NOT legally send funds to because they hadn't supplied us with the IRS required documents - and they didn't respond to our numerous communications to get them.Once we obtained the proper documents, we sent them their funds - by the way, we did send monthly Owner Statements, so they had the info to see what was going on with their portfolio.So, that brings up another question - what information have they been sending you and when have they been communicating?

Because the cosigner is not responsible for mowing the lawn or reporting maintenance issues, they have no rights to the rental, and I don't want to communicate with them about anything but the money. 

I have onsite management, but I manage reservations and communications remotely (and I have a full time job, so I really need the software to keep me organized, not the other way around, haha!).  

These types of tenants often do this because they don't want to save in advance, so they take the rent owed to you and use it to put down on their next home.Recommend you do a better job of communicating to the tenants that you will pursue every legal collection option if they don't pay last month's rent.Also, why are tenants NOT staying with you?

You might Want to try opening verbal communication with the owner ahead of time.Perhaps having the owner come over and look at the things you took pictures of ahead of time, might/ might/ be an intelligent thing to do.

My property management has been good about day-to-day items like appliances and turn overs, but poor at comprehensive solve like exterior leaks and only one individual has been good at communicating with tenants.  

Communicate: Depending on your options, consider having a face-to-face conversation with your tenants.