You really need to make sure to identify where the critters are entering the property and use spray foam to close all gaps.Also, I'd be hesitant to use poison inside.

Purchase price: $13,100 Cash invested: $30,000 Sale price: $79,900 This was my first fix and flip, The house was in complete disrepair, it was gutted to the studs, spray foamed, new electrical & plumbing. replaced the water heater and furnace with new high efficient models, new drywall & siding, porches, basically the whole house besides the roof and studs.

I was able to make an absurd amount of money by swing trading and doing a ****-load of research an i niche, highly unusual asset class (a company that effectively had a monopoly on oddly-shaped foam pieces/packaging for computer hardware during the PC boom).I was 8 and didn't know any better, so got out at 9 and saved it all.

Expect to go to R-19 or switch to foam. 

If I were doing this, I would definitely go with an air-impermeable spray foam -- sprayed tight to the underside of the roof sheathing to the thickness required to get the code R-value. 

You should have at least R30 in the ceiling/attic and unless you're doing expensive spray foam you can only get R23 out of a 2x6 bay.

With that many units I would definitely speak with the store manager at the big box stores to see if you can shave your costs.

Hi Tristam, I unfortunately can't offer any commercial insurers as for you but would like to comment on the loss...I'm not sure if Carrier denied this claim entirely ; if they stole wiring that would be considered Theft however I personally would consider the damages caused to the property Vandalism; in order to remove the wiring they had to gain access to the wiring and that would have probably damaged the sheetrock wall, damaged/scratched the paint, debris on carpeting (maybe metal shavings from wiring in carpet) and possibly even caused damage to the front door to the home to gain access.  

@John S. Have

That's why I always buy solid wood doors so that we can shave them down to fit into the door well.