I already am paying them for pest control, but they recommended sealing gaps in the home, installing a plastic barrier, and doing a termite chemical service.

Unless your lease specifies that you use poison control and that any risk to a person's pet is their responsibility, I don't think you can ethically (and possibly legally) create a toxic situation for pets that you've allowed in your units. 

Once you scale larger and your cash flow and the volume of work is there then you can higher in-house something you want to more control of but don't want to do yourself. 

Too much risk during a project of this size.You need to take control. 

The potential tenants are aware that I'm the PM and neighbor.Rent: $1,600Tenant 1: a few years about of school, excellent previous landlord references, two jobs, seemed clean cut and put together, Gross Income to half / full rent: 6.77x Half Rent / 3.3x Full RentVolunteered dad (well qualified cosigner) who agreed to be cosigner and passed all screens.Tenant 2: Similar life status and feel as Tenant 1, lives with parents (no rental history), toured apartment with his mom, Gross Income to half / full rent - 3.6x Half Rent / 1.83x Full Rent.Would you require a cosigner for tenant 2 or is tenant 1's dad enough when combined with both incomes?

Unless your profit margins are large you will be losing money and a peace of mind, won't have any control over the processes, and probably not be very high on a prop. manager's list. headache no mater how you slice it.

Combined use, condos, 1.5M flips, etc.For cash flow, you need C and D areas unless you have a lot of cash (B areas) and all you need is tax shelter and inflation control.   

My question is whether it makes sense to pay that premium in order to control all the duplexes and have the ability create my own feel for the drive, while not needing to nudge him about keeping his place tidy etc, or worry about splitting road repair costs.

I would never allow a daisy chainer to take control of any of my deals.

Anyway, I am here because I have a great retirement coming, but I have decided to take more control of my life and find a way to retire before I am in my early 60's and probably beat to s4it.