She is extremely rude, constantly bothers us about coming in to just fiddle around multiple times a week(with proper notice), and has been trying like crazy to break our lease.

Just another thing that can break.

The spreadsheet we use breaks out repair costs, etc and it's how we come up with our offer price.

What are my options, and can anyone break out the install cost? 

This will depend on how you breakdown your costs, but at a minimum, flip costs are broken down into Acquisition Costs, Rehab Costs, Carrying Costs (or Holding Costs) and Selling Costs, and you can break it down further (into sub-accounts) if you'd like.

If I do a regular refi I will make 300-400/m cash flow vs breaking even(living for free though).

Furthermore.... this “extenuating circumstances” dead uncle system is an easy google search for any guest looking to break the policy.

I have been a follower of the FIRE movement for years, now a long-time "mustachian", and have done what I've needed to in order to keep expenses low for myself and my family, but have done so in order to just break even.

People can't control a lot of things: car breaks down, tenant or kids get sick requiring them to miss work, reduction of hours at work etc. and I don't think owners are jerks by requiring tenants to continue to pay their rent through those instances. 

Tax break in the coronavirus stimulus package?