The storage services offered at various facilities can vary widely.  Some places permit parking, band practice, large trucks, and even commercial spaces.  Others have wireless internet, business centers, coffee, dumpsters, and online bill pay.  Make sure you verify the convenience of the facility before you rent.

Climate controlled storage can be your best friend.  There are certain times of year and areas of the country when you would be highly advised to get a space with some kind of control over the temperature within the space.  If storing wooden items, electronics, artwork, and any other fragile materials, consider paying a little extra each month.  You wouldn't want to go through all the trouble of storing your valuable only to have them damaged by poor climatic conditions while being stored.