The IRS generally requires improvements that add value, prolong the property's life, or adapt it for a different use to be capitalized and depreciated, not expensed.However, as you mentioned, you might be able to expense the resurfacing under the De Minimis Safe Harbor election if the total cost is $2,500 or less per invoice/item.

I am 6 months in and he just prolongs my project.

I'd avoid doing this in units with shared ventilation as there is a potential risk of irritation to someone's lungs with prolonged exposure, especially if the person already has existing lung disease.Ozone machine will run about 60 bucks on Amazon.

If you wait, then you prolong future repairs.If you are good with what you have, enjoy living there and do it after.

There are cost tied to prolong rehabs. 

They had been able to do this for a prolonged amount of time since the economy was still proving to be relatively good based on unemployment figures.

If your tenant prolongs their stay one month, you've probably cost yourself more than what the attorney would have charged.

Bankruptcy saves the lenders from losing even more money during a prolonged foreclosure.

The longer you take the longer it will take.I'd rather a $1000 loss than to prolong the situation and lose the grand along with several more months of possible rent and aquiring more and more structure damage to the property.

Any lower than that for a prolonged period and it will freeze up.