New roof negotiated into purchase.

Think about an HVAC, storm damage, paying for housing if a tree falls on the roof, dealing with stupid insurance companies, etc.

Maybe do a fireplace on the outside way and run the vent to the original outlet in the roof.

Sagging roofs and purlin retrofits.

Let's talk roofing. 

A full gut and roof HVAC windows etc for 100k seems very low.

it is all good , who knows who under your roof if you don't tell

Of course, there is the lifestyle aspect.

Until you have to do a major repair like a roof.  

Try to anticipate other potential avoidable situations with a follow up inspection to assess the Locksmith’s work and ask your tenant(s) if you can also use the time to assess for other issues such as unchanged HVAC filters, leaky pipes, working shutoff valves, working smoke detector batteries, properly working downspouts, clogged dryer vents, evidence of water damage from leaking roof, etc,etc,etc.