@cwal No You do not have to change the whole unit yearly just the handpiece yearly and change the mesh piece 6 monthly, I think the handset incl the mesh head is around $200 $NZ, cant remember how much the mesh is on its own, no idea what prices in the USA would be. But the ebase controller and power supply last for many years, I bought mine in 2017 and it is like new. I know of someone who had their pari for 20yrs, would have been an older model tho. It has been so worth the money for me.