The biggest challenge in renting equipment (other than actually acquiring the customers in the first place) is that anything you rent out gets destroyed quickly, due to transport and whatever setup/teardown you have to do. A piece of equipment with a 5 year lifespan may be designed with the assumption of 1-3 transport/installations over the course of its entire life, and here you are moving and reinstalling it every week. Not to mention, your customers will be less experienced with using it, so they are more likely to break things.

The key to being able to compete with larger rental companies on price and reliability as a one person operation, is to rent out something that you know how to work on. This will give you a big competitive edge because you don’t have to replace anything or hire expensive third party repair services for basic maintenance and fixes.

Large work site equipment like generators and stair climbers could work. You could also do event stuff like sound systems and stage lights. You could do boats or work vehicles. Camera gear is a hot one, but my god is it fragile and expensive.