Here are some options. All of these have thousands of searches per day on Google:

trailers, campers, lifts, scissor lifts, cherry pickers, dumpsters, storage pods, scooters, wedding flowers (yes), game buses, boats marquee letters floor sanders deck sanders sandblasters aerators …and other heavy tools generators hospital beds portable restrooms dresses maternity dresses prom dresses sweet sixteen dresses accessory dwelling units sheds autos (thru Turo) dollies outdoor heaters yurts mini excavators trenchers Bobcats skid loaders …and other small machines TLC plates transmission jacks atv’s wheelnchairs washer dryers throne chairs horses dogs home staging furniture

Yes. This.

It’s not unanimous advice. And it’s only one way to achieve success. The vast majority of successful entrepreneurs DO NOT FIND A PROBLEM etc. Instead, they simply become another market participant in an already thriving market. They become a plumber (already thousands of those), or they open a dropship store, amongst thousand’s already existing, just to name a few examples among many.

You don’t have to think up something new or unique.