You will have to some way of storing files and paperwork in your home office. Cardboard boxes while useful are not effective nor efficient. Depending on the level of security needed for your work, you may have to have a locked filing cabinet or perhaps a safe. Your are better to spend money on a quality cabinet and/or safe then to be replacing them every couple years.
Mobile file carts are a great solution for telecommuters. With some mobile carts it is even possible to bring them back and forth between the home office and the corporate office. Ease of use and room for a variety of sizes of files is a big factor when considering a mobile file cart.
If you have the space and the need for this kind of storage, lateral filing cabinets are a good solution. If you think that you will require more space down the telecommuting road, it's a wise investment to buy a larger cabinet at the beginning. It's much easier than trying to find space for another cabinet later.
Vertical cabinets are great for storage and 2 drawer units can be tucked under workstations to make use of the dead space in that area. When considering vertical filing cabinets, keep in mind the space you have available in order to determine if a 2 or 4 drawer unit is best. These cabinets are fireproof which is an added benefit.
Everyone should have a safe to keep back up disks and other important files safe. This size of safe you require will vary depending on your needs. An important reminder - keep a copy of the combination or spare keys in a safe location away from your home office, such as a bank safety deposit box. In the event of a fire or other disaster you can still get access to the safe later.