I’m considering having a lawyer send them a certified letter, though I know that will still come with a significant fee, which is still preferable to full service.

You will get away from income taxes and annual registration fees by going to the townships, but your property taxes skyrocket which may offset some of the rent increases.

Might be a way to get some cash quicker or maybe get a buyer for the land quicker if you can show them they could pull 1k an acre by having someone come clear cut the parcel after they buy it.The local population seems very limiting too.

Remaining money (less title fees) in escrow is returned to wholesaler (less PML funds and fee if used) with the remaining from the Step B contract.

I have bought notes based on bank saving time legal fees and property damage during the foreclosure process, if you were buying residential paper I would look at the foreclosure timing first if it is like Wisconsin you can get the banks attention if it a very fast moving process like I am told florida is note purchass can be difficult

1.7 % of Loan Amount (Points) - $6,035underwriting fees - $1,400Are the above fees reasonable or not for refinancing a mortgage?

Just call a local title company, find one with good reviews, and ask them to give you an idea of the fees. 

For example, I mention that every adult must pay a $30 application fee, pass my credit/criminal background, make a combined income of 3x the rent, and whether or not the property accepts pets.

Can be a good strategy, but my understanding is BRRRR is generally dependent on refinancing and pulling back that cash invested to repeat the next one

Why do you have 24k in cleaning fees as expenses for an STR?