Some cities require the STR permit number in the title or very top of the OTA listing so city permit  technicians can scan and keep track otherwise the owner will be contacted and fined for forgetting or shut down if operating illegally.Some cities have a 24/7 STR hotline dedicated to receiving any complaints (from neighbors, HOA) for a code compliance officer to act onSome cities issue expensive fines for those operating without the STR permit

This way you have a larger paper deduction during the early years owning the property. 

But agree that the condition of the roof could be an issue for your lender and your potential insurance carrier.

You will need to supply 2-3 quotes from different General Contractor's or licensed builder for all work.Some things that can occur are builder/vendor issues with lack of inventory, broken material, employee "no shows", date of completed work extensions, bad work, additional costs not factored on blue prints or cost analysis, delayed permits.Keep in mind any delays or issues will slow down your clear to close/funding date.

In Oregon (not just in Portland) you can't preemptively issue a no-cause eviction due to a property sale unless you have an accepted offer.If you are going to make an offer to the tenants to move out early or prior to your property going up for sale that offer can't be for less than what they would be eligible to automatically receive via Rental Relocation Assistance.

Also, told me money is not an issue but in the same breath asked if they could give less than 3 month's rent to move in (I had already explained the requirements). 

The larger property will be required to be held in an LLC.

If during the next 2.5 years, the owner redeems the property i get the money + interest back, but lets say they do not redeem the property. 3)  Within the last 6 -3 months of the expiration of the redemption period, I will file a petition at the circuit court for the tax deed 4)  At the same time, after filing the petition for deed, I will need to send "Notice of Expiration of period of Redemption" Take Notice to the county so they can mail it to the home owners and any interested parties informing them to redeem asap. 5) I will subtax early the following taxes as soon as they are generated by the county. 6) Inform the property owner in three ways, certified mail from the Circuit Court Clerk, being personally served by, the Sheriff’s office; and notice being published in a local newspaper. 7)If the taxes are not paid and the last date to redeem passes, the tax buyer can apply to the Circuit Court for an Order directing the County Clerk’s office to issue a tax deed to the tax buyer.

I have done a lot of research on this issue and the bottom line is yes, you can require that your tenants have renters insurance.

Plus, the safety issue with the kids leaning on those windows?