You might want to call a couple dealers, talk to the rental manager, in your area and ask the why they don't offer sweepers /scrubber rentals, based on their websites. Two I have had past acquaintances with that do or did represent Crown Lift Trucks. Thompson Lift, headquarters in Birmingham, Ala & Daily Equipment, (Pearl I think) LA. I only mention Crown because they do a lot in in warehousing & warehouses generally like to keep their floors clean. Check with you local Raymond dealer.

There is a guy on this site, FAC screen name starts with BudOne (I think).... or some name close to that works for Thompson & is very knowledgeable , maybe he will chime in on this thread.

Just recalling comments dealers i worked with in the past mentioned that scrubbers, sweepers are a high maintenance products - like any thing that plays in dirt does, brushes & squeegee rubbers. The parts department loves them keeps up their parts sales, kinda like skid steer loaders - they are "parts eaters" which means - maintenance costs are high - this has to be recovered in your rates. Secondly, a lot of warehouses do floor cleaning in "off peak" work hours - supplying rented operators might be an issue. To start up your idea you need to factor in the costs to buy support services from a second party - things like pick-up & delivery of equipment, some one to do regular maintenance & repair work, warehousing of rental products and some of on the shelf parts inventory to keep the machines "up & running" & back-up equipment when machines are down for an extended period.

Do you homework, calculate all you expected costs and figure out what you need to charge your customers for your services (including product liability insurance) then add another 20% to cover some of those "non expected" costs - then approach your prospective customers to see if they are will to pay. There are reasons why dealers will not rent with maintenance to places like "pickle foundries" or "meat packers" at best the do maintenance on a time & material basis - which always call for a lot of interesting discussion with the customers.. Also this often why companies want to shift their costs & responsibility to keep their floors clean to someone else at a lower cost than what they have experienced.

In the end if you determine can make a buck don't jump in with both feet and put everything at risk that you have worked for so far including the pictures on your homes wall and your Callaway Big Bertha golf clubs or Ranger Bass Boat - start out slowly.

Just my 2.4 cents worth - if you want to trash can it that is OK won't hurt my feelings.