If you make alterations to your apartment that can be construed as fixtures, by law they can become the landlord's property. The determining factor is whether the appliance or addition in question is permanently attached to the property. If so, it fits the definition of a fixture.
If you aren't sued for a violation of your lease because you made an unauthorized alteration, when you vacate the unit ownership may pass to the landlord. For example, if you install track lighting, a washer machine or a dryer, you may have to leave it there when you depart, even if you got permission to install it in advance. In many, if not most instances, ownership passes to the landlord once you affix the item to the property.
If you want to keep whatever you put in, it's best to have a specific agreement with the landlord to that effect. Have a qualified Landlord Tenant attorney review it before you sign it.
The New Appliance Ding
On the other hand, if an appliance in your unit ceases to be functional, and your lease is rent-regulated, the landlord is obligated to replace it. However, if the replacement appliance is brand new, you can be hit for a charge of one-fortieth of its cost every month for the balance of your lease. This additional expense will be reflected in all future rent increases.
In addition, you may sustain the cost of necessary modifications to the apartment to accommodate it. So for example, if you get a new stove or refrigerator, certain electrical adjustments may be required so that it can function. You will have to pay one-fortieth of that cost too, as an ongoing rent increase.
If you don't agree to a boost in rent for the new appliance, you can avoid these charges, but may have to make do with a used or reconditioned one, which may not be ideal. If the landlord doesn't have a used appliance to supply you with, the issue may be argued, but you'll probably end up in Court. Your legal fees may exceed the cost of the rent hike you would otherwise have to pay.
Rules for Special Fixtures and Attributes
Existing laws also encompass unusual attributes in an apartment. For instance, if you rent a unit with a unique feature such a fireplace or Jacuzzi, or even a washing machine, the landlord is responsible for maintaining it in good working order. If the fixture or appliance was present at the beginning of the lease, then even if the lease contains a clause waiving the landlord's responsibility to maintain it, he or she still has the obligation for repairs.
But, if you are negligent in the manner in which you use the fixture or appliance, or if you alter it in some way, the landlord can be excused from repairing it. You will then have to pay the cost of fixing any damage you are responsible for.
Before you change anything in your apartment...
The smartest thing to do before you alter your apartment in any significant way is to consult a knowledgeable Tenant's attorney. You want to get the right advice on the likely outcome of your landlord's response, and an idea of the costs you'll sustain. With professional legal guidance you can also avoid giving the landlord a reason to sue, and potentially evict you.