They/you can't choose the carrier - their software assigns it.Fortegra is one of the carriers (paper in insurance parlance) that their product is written on.That said, Fortegra is A- rated I believe by AM Best so that isn't the issue.I'm going to take a guess and say that your umbrella is written with PersonalUmbrella.com (Markel) and they require all underlying insurance to be A-rated but also with an admitted carrier. 

On a more enterprise scale, I employ RevMax software as well as a fractional revenue manager who looks at the prices daily on a market level and a comp set level. 

Never signed up for his program, but you don't really need his software to do section 8.

If I have to manage the property by myself, I am curious which property management software (Hostaway, Guesty, Lodgify, PriceLabs, Hospitable) is better for sending check-in, checkout messages, and other automated messages.

The simple reason is that you cannot even tell debit cards from credit cards without a special software.

I have ~20 doors in OH that I self manage (there are some awesome softwares out there now for self management) and am looking to start investing in Buffalo too.

If you decide to go the multifamily route, Real Estate lab .com is a multifamily software for deal analysis plus they have many other useful features. 

Whether you need a CPA with just three rentals depends on the complexity of your situation and your comfort level with DIY tax prep.If things are pretty straightforward, you might be fine with tax software for now.

Lots of flooding and rain.  

We Normally put steel posts nearby so no one runs into them.In the third picture one unit is just in front of the picture, then a second unit is at the far end on a post.These can be set off by deep fog, rain or sleet.