I fix a lot of things, so if it were my rental I probably would try to take the light apart and figure out what's wrong with it.As for the warranty idea, I try to buy with a credit card that provides an extra year of coverage on items that come with a warranty.

I have raised half of the units to market value of $495. 

Have you considered Credit Card financing? 

However in the time that they’ve lived there their rent has never been raised.

The house of cards will come crumbling down at some point.

My CPA told me if her name is on the card it wouldn't be an issue, is this true?

If you can do that, you'll save $20k/year and add about $285k or value (with a 7% Cap Rate).Is there opportunity to raise rents?

You raise $5K/door (or more) upfront to address deferred maintenance and value-add improvements.

As has been said, you past the cost on to the consumer, and raise the rent rate (while advertising that these utilities are included in the rent). 

@Tanya S.The realtor said a lot of what you all said, price low and let the market raise the price to what it will.