Free Parking, NOT Storage!
Private parking for tenants is one of the most common amenities in an apartment complex. After all, wouldn’t you want to park as close as you can to the place you are renting? Assuming you provide your tenants a parking spot, you might notice items left in or around their parking spaces. Aside from obstructing neighboring spaces, it can be a misuse of their parking space as well as a fire hazard.
This is not really a problem if it is something small: you can tell them to leave it in the trunk of the car as an alternative, or if the building happens to hold accommodating carport types of parking, you could think of adding value to the lease by installing wall mounted storage cabinets that are perfect for storing oil equipment, car jump starters, etc.. The real problems come from larger items: rolling car jacks, extra tires, and barbecues. In some cases, another vehicle is small enough to fit in the space with the main vehicle (motorcycle, etc.). It is also very easy for tenants to deny any ownership of any items found there. This can be a problem; for example, if you find drug paraphernalia in a parking space, a tenant can deny they have any connection to it. After all, people litter and leave things around all the time.
The best defense against these issues is to define the misuse of the parking spaces in the lease. If you have not added specifics to the lease, you are allowed to add it in so long as you give notice and provide ample time for tenants to clear out the items (timing can vary depending on lease agreement: a month-to-month lease would require you to provide at least 30 days for a tenant to clear out the items). Angrier tenants may request to see a fire code violation report if it directly interferes with tenancy. Make sure to have that on hand if asked.