I've appraised self-storage facilities and these are generally multi-million dollar properties. You can get one for "cheap" (i.e. less than $500,000) if it's old, small, and/or in a rural area. However it's like a small apartment complex where it's not cost effective to have an on-site manager and you would probably need to live on-site and manage it yourself. I've seen a few new ones built in my city in the last year despite there being dozens around already. One I appraised sold for $13 million, another for about $17 million. Even at 70-80% occupancy these are still profitable and most will operate at 85% or more if well managed and in decent condition. In the last few years a lot of institutional investors (pension funds, REITs, etc.) have started buying these properties and in many cases the yields are comparable to a quality office building or shopping center.
I'm amazed when I look through the rent roll and see people who have been renting a storage unit for 5-10 years or more. I've used one once when we moved to another state for about five months while I was going through some Army training. We were going from a house to an apartment and didn't want to move a lot of our furniture, books, etc. If you have to rent a storage unit to store extra stuff, unrelated to a move, it's a pretty good sign you need to get rid of some stuff.
One owner/manager told me about an elderly person who rented three large storage units to store all the belongings of one of their adult children who had died. The were paying probably $600 a month for multiple years just because they were avoiding going through that stuff and either selling it or giving it away. Had they simply kept whatever mementos had meaning and then had an estate sale they could have been done with it in a week or two and probably made some money instead of throwing away thousands every year.
