My grandfather had 5 rental houses at one point that I helped rehab, but unfortunately he passed away before I was able to pick his brain. 

You might look into something like a thermostat plastic cover/lock option, but again if they want to reset the wifi box that bad, they probably know how to YouTube lock picking and can easily open up a basic lock box type lock.A lot of the wifi systems these days allow a mesh type network to allow for more coverage.  

Here's my advice- I find its easier to pick a market when you get an understanding of a criteria.

Looking for some good tips for picking a tenant pre/post Covid if there are any differences at all.

She told him to pick his best and final for all properties.

This was my first real estate investment so my goals were fairly conservative, I wanted a balance of cash flow and stability so I picked a modest sized 3/2 home in a B neighborhood in my market.How did you find this deal and how did you negotiate it?

With the historically low interest rates we're seeing now and the potential turbulence that may come in the next couple years, savvy investors are making sure they can ride out any potential storms without having to refinance at a time when the loan market is way less favorable.Best advice is to get a good commercial and residential lender (likely different people) in each market you're looking at and pick their brains about what's possible right now.

You can also pick up the phone and call a local commercial MF broker and ask them. 

I really want to use the BRRRR strategy, so picking the right property is vital. 

Have you picked up David Greene's BRRRR book?