Do you think the rising taxes might eventually become a bigger concern, or do you feel the benefits will continue to outweigh the costs? 

Here’s a refined version of your message that maintains your original questions and concerns while improving clarity and flow:Hello,Since January, I haven't received the full rental payment from the property management company.

I’ve been looking into coastal options and was initially considering Florida, but the taxes have been concerns. 

My concern for you is that it appears that if the owner comes back, they only have to pay the bid amount + costs, not what you paid for the broker.

My concern is whether the city could deny permits for these modifications, such as removing walls or converting a garage, or if they are mainly just concerned with safety and habitability.

Basically the concern is they tie up the property, collect enough rents to make a little bit, and then just default.

I do get you having some concern maybe going into winter in WI and wondering if tenant activity will be there to fill a vacancy (with lots of leases and moving around happening spring-summer).  

I’m not terribly concerned about the house since the layout would make it easy to survey & subdivide to make it two parcels.

If you have one abuser, it won't affect everyone else systems.One thing not mentioned that could possible be a concern is were they are placed. ie. are they all positioned well for inspection and/or replacement if need be?

If cash flow is a concern it's a big one usually