What is a tenant's duty to repair?

A tenant has a duty to not allow the property they possess to fall to shambles through neglect. There are essentially 3 parts to this. The first is that they aren't allowed to commit waste. If you've made it this far, you've likely already seen waste discussed under life estates, and it's basically the same for tenants (though we'll cover it in separate cards).

The second part of this duty is to make ordinary repairs. Obviously "ordinary repairs" is a fairly broad concept, which means you'll need to argue it on an exam. But think of "ordinary repairs" as those things that don't take much effort to do but prevent larger issues from happening. For example, replacing a leaky roof on a house is not an ordinary repair, but plugging or fixing a leak in a roof is. Likewise, fixing a leaky window likely is. The law doesn't expect the tenant to unjustly enrich the landlord, but they are expected to not ignore issues that can become big problems. Other ordinary repairs may include hiring a plumber to fix a sink that the tenant clogged, or cleaning grease off the stove. Keep in mind that a tenant need only return the property to the landlord in the condition that they accepted it, so "ordinary repairs" would be any that meet that standard.

Finally, the third part is to be clear that tenants are not liable for "ordinary wear and tear". What is wear and tear? That's for you to argue on the exam. Generally speaking, wear and tear is the normal and unavoidable evidence of use that occurs when a property is reasonably lived in. For example, a few stains on carpet are normal wear and tear. Dirty grout, or a few scuffs on the walls are also wear and tear. In other words, the hole in the wall that was caused when your buddy did a drunken handstand in the living room: you need to pay for it. But the scuff on the wall that was caused when you moved a chair? That's the landlord's problem.