This would typically still cover any damages to the house itself, and any liability for owning the property, but would no longer cover the contents of the house, which is a fairly large line item within your owner-occupant coverage. 

Best you speak with several licensed electricians to get inspection/quotes.Just an item:  to convert a 110  system to 220 (at the box) a ballpark price would be $2,500+/- with all permits and inspections.  

I would also add that perhaps there's more improvements that were made throughout the year that OP maybe isn't considering (even like little items).in addition, items at closing (both at purchase at sale) also affect your basis in the property/gain on sale 

That is by far and above the #1 item at play here. 

Paint, maybe some new light fixtures, some low item updating etc. 

I'd say definitely factoring in the depreciation, age, as well as if they actually made effort to have it professionally cleaned.When back charging things from their security deposit, you have to provide the tenants an itemized list of what the charges are for...

What are the consequences of failing to disclose items such as unpermitted additions in a property disclosure agreement after a flip?

You should have a minimum of 5-10 ranked items on this list.

Document the items to be repaired and the cost and deduct from the security deposit.

FYI: My lack of replies and follow up to other items your saying isn't a lack of interest or disagreement, it's that I have total agreeance and have no way to add anything further of value, you wrapped them up perfectly.