After dealing with going through residential grade mowers that just keep braking down constantly every year and lasting maybe two, I just placed an order for a Toro 22198 and an Exmark Commercial 21 X series with the Kawasaki Kai. I might also have a zero turn and a 36" walk behind on the way once business picks up and if I get larger lawns. My question is how long should a typical commercial mower last, being a 21 inch, walk behind or zero turn with proper maintenance? My dealer said with proper maintenance I should see ten years out of most commercial grade mowers with few if any problems, but I though I should get a second opinion. Also any extra tips to have your mower lasting for as long as it can?