Take a look at the things you plan to put into storage. You may already have an idea of the size of storage unit you want to rent, but keep in mind that you don't want to just rent a storage unit that will fit all of your items, you want a unit where you can fit yourself inside with a little room to work. If you ever want to be able to get your items out, you don't want to pack your storage space wall to wall, floor to ceiling. Many people get the smallest possible unit they can get in order to save money, and then wind up having to empty half of it to get to a box that's in the back. Don't be that guy, unless you know you'll never need anything you're putting inside.
Now we're going to focus on how you can find the right storage facility as opposed to keeping everything at home in storage boxes overflowing in your garage or attic. Here are some things to do before you even pick up the phone.
Don't get stuck on location. First, don't get stuck on the storage facility closest to your home. There's no faster way to find yourself storing your precious memories in a facility that's inadequate than to get stuck working with the one that just happens to be closest to you or cheapest in your community. Cast your net wide enough so you have a good handful of options that you can investigate.
Check the reviews. Look up the storage facility on Google. You obviously want to take reviews with a grain of salt, but if they're all bad or there's a recurring theme, you may want to steer clear. The reviews can also give you some insight into what you may want to keep an eye out for if you go visit the storage facility.
Compare the gate and office hours. A number of storage units only post their gate hours, to make the location sound like it's open later than it really is. Remember there's a difference. The gate hours are usually the hours in which you can access your storage unit, but the office hours are almost always shorter. If you have a problem or need to speak to someone, you'll only be able to address your issues during office hours. Similarly, make sure the gate and access hours are convenient for you. If your storage unit closes at 5pm on Saturdays and Sundays, it's probably not very convenient.
Now that you know what you're looking for and you have a few options, it's time to go take a look at the storage locations you're considering. Once you walk through the door, don't be pressured to sign on the dotted line right away, even if the property management tries to tell you that units are limited. Most companies will let you at least hold a unit overnight so you can think it over. Make the most of you visit by looking around and asking questions instead.
Ask the property management if you can see the unit you would actually get. This, or at least a unit on the same floor or in the same area. Some storage facilities will show you a clean, 3rd floor unit but actually rent you a dirty, bug-infested basement one, so be assertive if you have to so you can see a unit representative of the one you'll actually sign for.
Ask if there are any rental specials or discounts available. Most storage companies offer specials from time-to-time, which makes the transition from an old storage unit to a new one really easy (especially if you've already paid for the last month in the old unit) or if you want to make moving into the new unit a little less painful on the wallet.
Find out what happens if you miss or are late on a payment. In many places, storage units aren't treated like apartments. On the first day of the month, your rent is automatically late. Grace periods vary by the company or even by the state, and in some cases even being a few days late with your payment means your unit's contents can be auctioned off to the highest bidder at a wholesale auction. Check to be sure the property follows your state's lien laws in these situations. Make yourself knowledable and look up your states laws to see what you may have to deal with if the situation ever occurs.
Once you've seen the unit you would actually get and you have a good understanding of what you'd be getting into, ask the property manager if you can put the unit on hold if you like what you see. They may or may not be able to, but don't fall for high-pressure tactics. Even if you can't hold the unit, get a business card so you get back in touch with the person you met.
Hopefully, this helps you to find the perfect storage unit and hopefully that storage unit is ours!