We are on the long term rental side of things.  

This pre-2023(I am not counting 2023 REI in this as it's too early).

What insurance are you all using for furnished medium term (30 days and more) private room rentals?

You should NOT "help" the seller in certain circumstances, no matter how pure, sincere and full of Godly intentions you are, if they are in foreclosure or pre-foreclosure and live in the state of MD.

Yesterday morning he said we should have the final terms by end of day. 

Having a Pre-approval letter or better yet a loan commitment and a Banker to call and reassure the sellers agent you can close in 30 days or less also offers a huge advantage.In this market using a DPA is not a bad idea since rates are high and when they drop you simply refinance for a lower rate and payment. 

My properties acquired in pre-2013 are doing well and they kind of fell in my lap.

Has anyone had good or bad results from trying out credit report and score businesses that aim to improve credit and help in the journey to gaining a pre approval for a mortgage?

What type of terms they looking for?

I grew up in Memphis where I own 4 long-term rentals that are SFHs.