Change the air filters, make sure sprinklers are set and watering, landscaping done, check on cracks and leaks, visually inspect roof, also checking for pets, and how many people living there. 

Some common items to note: roof, electrical and plumbing, window updates.

We had an leaking issue in the last post when the previous tenants stayed for their last two weeks.

So the house wound up needing the drywall, kitchen, bathroom, roof to the garage, Plumbing, Gas and other stuff done. 

Costs the same to put on a new roof. 

In fact I'd guess you could probably structure a discount into your agreement just because of the logistics (no roofs, no foundations, no yards). 1031 isn't a terrible idea but you've got a few hurdles outside of costs - you're going to have to have some possible properties already identified as your window is small, you'll still have to manage the property unless you go through a PM, you'll lock up more/most of your principal since you're going 'bigger'.

The roof and HVAC will need attention first.

Traditional roof.

For example, making an owner aware that they will likely need to replace the hot water tank or the roof within the next 12 months if they're in visibly bad shape.

renovation including a roof replacement Did you work with any real estate professionals (agents, lenders, etc.) that you'd recommend to others?