The square footage of the unit is one of them. If you rent a big unit then you will pay higher amounts of rent and yet the space is not serving you well whole a smaller one will, be inadequate. Check out the prices charged for the storage units.
The location of the storage facility is another thing, normally storage facilities that are located in larger cities tend to charge a premium for the services while those further away are cheaper. In case you rarely need to check in the items you want to store then you can select a unit that is further away from the town.
The kind of items you want to store will also influence your choice, if for instance they are perishable items, then you should select a climate controlled facility. Besides if the storage facility is in a location that is affected by extreme temperatures, then you should choose a climate controlled facility. You should also look at the ease of access of the facility, if you want to be accessing your items often, then go for a place that offers 24/7 access. Security is paramount in a storage unit this is from theft. You can click for the best storage units or visit this site for more storage services.
A good facility should for example have a CCTV surveillance systems so that the security of the items stored is guaranteed. There should be security personnel too to keep everything secure. Fires are quite common in storage units, however, a good facility should have necessary mechanisms to counter that, for instance, sprinklers and fire extinguishers among others.
Another thing has to do with the amenities within the unit. The best storage unit to choose should be having ample ventilation which let in air to circulate freely at all times so that there are no molds developing in case of dampness. Finally the construction of the unit should be such that water cannot flow into the space and wreck havoc or destroy the goods there. You can read more on this here: https://www.huffpost.com/entry/how-to-cut-your-self-stor_b_7841538.