Self-storage.
Try not to start rental during the summer/spring, prices are way higher than winters.
If you're storing short term with items that are easily bought new, I would suggest just getting rid of them and buying new. I see a ton of people who store thinking they'll be out in 3 months and end up staying a year and spending way more than the items were ever worth. This is especially true for home renovations, those take up at least 50% more time than you think they will.
If you smell something funky throughout a large part of the floor, don't store on that floor. It's most likely caused by mouse issues.
Try to store in an elevator access unit instead of ground level. They're usually more secure, tend to not have mouse issues, and end up cleaner because they're lower traffic.
The dirty secret that nobody wants to talk about. Sometimes, stuff equals capability. This is especially true with tools, renovation supplies, and hobby supplies. That old drain snake in the garage? $350 plumber call. Rarely used winter gear in a closet? No $$$ rental on the occasional ski vacation. Sewing machine and supplies? Now you can alter or repair your clothes.
It can also be resiliency. All those extra Christmas candles? Great for a power outage during hurricane season. Buying, preserving, and storing summer produce can save money later in the year. A deep pantry can be a critical safety net for some people with job insecurity.
Of course, there’s still a lot of crap we can get rid of, like old hand-me-downs and things we’ll never use.
It’s really a balancing act between the cost of maintaining capability and the cost of paying for outside services. For me, I basically add an entire room to my house for $150 a month, and still get to keep the ability to do the things I love and have some resiliency in my life.
Maybe if you aim for the absolute bottom, but...I inherited my grandmother's house and belongings when she passed away. I own at least 90 towels, 20 sets of bedsheets, 6 sets of dishes including the sacrosanct "We don't even serve meals to god himself on those plates" "good china"...There's a lot of shit you can do without, or without as many of.