Our landlord(s) want to charge us $30 or $30 per car for parking. We have a garage and a driveway, but mostly have to street park. Just wondering the legality of that. We live in Dane County, Wisconsin if that matters.
If you began the lease with no mention of additional payment specifically for parking, and were of the understanding that you could use the property to park cars, and have been using the property to park cars with the knowledge of the landlord, and the landlord has not previously mentioned parking as a distinct part of your lease that carries a fee, you have a very strong argument that parking cars on the property was part of your leasing the property.
People park cars on their property regularly; it is a reasonable default assumption that unless told otherwise, you could do this at will. The landlord presumably knew you had been doing this and had not notified you that e.g. it was against an explicit part of the lease or was against a legal regulation to park cars on that property without a fee paid.
This is a request for additional payment for something you are currently able to do for free, and doing as part of an existing contract. Therefore, your landlord is offering a change to your lease: the rent will go up by thirty dollars or you will be barred from parking cars on the property.
In neither case do you receive additional consideration, so it may not be a legitimate change at all. Regardless though, you do not have to accept the false dichotomy: you can choose to continue parking your car on the property and not pay the money for doing this.
Do not agree to the change. Do not pay any additional money. See a lawyer that specialises in tenancy law for your jurisdiction and obtain their opinion before replying to the demand for a change in the terms of your lease; you may have access to free legal advice depending on where you live.
It is entirely legal for a landlord to charge for parking on his property. The law only gets involves when it comes to towing, regarding notifying police, signage and the need or non-need for a ticket.