He is extremely demanding that I fix and make any house modifications that he says and has recently told me that he has shut off water to the sprinkler system because it's a waste of money for him.Unfortunately, I do not have a specific lawn care clause in the lease.  

@Daniel Gearner,Perhaps a modification of your strategy would be helpful:1.

Thanks @Matthew Paul @Omar KhanRegarding cost segregation, are you referring to segregating the costs of toilets installations and other water related modifications so that they can be depreciated over 5 years instead of the norm?

So think Tornado necessitating a roof replacement vs roof replacement at the end of it's natural life... 

I would not be aware unless they request a reasonable accommodation or modification in the unit.Certainly, it may appeal to the smaller renter pool individuals who use a wheelchair, but it may turn off renters that don't require the modifications.  

I'm told this will necessitate a commercial loan which is probably in the 9% range in my area, right now.

In addition, after 27 years, there have been changes made in the sizes of the indoor equipment that will probably require sheet metal duct modifications to make it fit.

This is an egregious modification.

Then, have an attorney that you hire to protect your interest create a modification, that way it will be cheaper than starting from scratch. 3) a checklist and systems that make up your SOP's.  

I'm hoping to work out a modification with the borrowers to start receiving payments.