I just found a site called Hire A Fire Truck. Its a company that looks like buys retired fire engines and then rents them for different things like kids parties, weddings, and other  a events that want to rent a fire engine.

Most of it might be for kiddie rides. I have seen where a rehab builder will take a retired engine, remove the hose bed and water tank then put in bench seats then make doors that looks like the back end of a hose bed to keep anyone riding from falling off.

Plus they will add a sound system to the truck.

Other companies have taken Japanese mini trucks and built a pumper type body that is design to ride  people similar to the other design mentioned.

Maybe for some retired firefighter it might be a way to make some money by looking into these types of bussiness.

I seen another idea where someone built fire truck limos using real fire engines. They removed the pumps and tank and built a tricked out seating area in the body of the engine. The chauffeurs dress as firefighters as part of the service.