A commercial grade lawn mower should last between 2,000 hours to 3,500 hours or around 4 to 7 years although some commercial grade mowers may last even longer and may go as high as 4,000 to 5,000 hours or even 10 years or more.
Commercial grade mowers often last longer than residential mowers and some mowers last longer than expected with proper care and maintenance.
Gas powered lawn mowers will often last for 7 to 10 years or around 1,000 hours to 2,000 hours although some lawn mowers may last longer depending on the quality of the mower and how well maintained it is.
Often 1,000 hours is considered to be a high number of hours for a residential lawn mower engine even if it's well maintained.
And some commercial lawn mowers and especially lawn mowers that have stronger engines and better construction can often go for 2,000 hours or more.
A lawn mower typically lasts 7 to 10 years when properly maintained although some lawn mowers that are not properly maintained or see a lot of use may only last 5 to 6 years and some lawn mowers can even go 15 to 20 years.
You should only need to replace your lawn mower when it has worn out or is in need of repairs that cost more than what the mower is actually worth.
If the lawn mower only needs small repairs then it can be worth fixing and keeping but if the lawnmower is getting older and needs constant repairs then it can be better and often cheaper to go ahead and replace the lawnmower with a new one.
This especially true if you run a lawn mowing business as you need a reliable lawn mower to perform the lawn mowing without worrying about breaking down.
Depending on the quality of the lawn mower you may need replace your lawn mower as often as every 7 to 10 years or when it's showing signs of wear and tear and it gets to the point of not being worth fixing.
As long as you maintain your riding mower mower push mower it should give you 7 to 10 years of use.
I have a push mower that is 20 years and it has a Briggs and Stratton engine on it and I change the oil yearly and it's ran fine for those 20 years and is still going strong.
I also have a riding mower that is 20 years and still operating fine.
Some people need to replace their mowers sooner but as long as it's running and mowing there's no need to replace it unless you run a lawn care business and need to ensure you have a reliable mower.
The best zero turn mower for the money is the Ferris Z3x 61" however they are expensive mowers.
The Wright ZK is also a great Zero turn mower.
John Deere Zero turn mowers are also great as well as the Ego Power+ 52" Z6 Zero Turn riding mower which has a 52 inch mower deck and also expandable battery system.
Another great zero turn mower for the money is the Cub Cadet Ultima ZT1 which combines raw power with extreme comfort.
The best riding lawn mower for hills is the cub cadet ZTS2 series which is rated for up to 20 degree slopes.
I use the cub cadet ZTS2 series at work in lawn care and use it on 25 degree slopes and it feels solid and does a great job.
It's not mine but my bosses mower but I would highly recommend it for hills and steep slopes.
Other best riding lawn mowers for hills and steep slopes are the Venntrac and Steiner mowers.
However these are more expensive lawn mowers and most newer lawn and garden tractors do very well on steep slopes but you also have to be careful.
The Kubota lawn tractor or X500 JD is also a good option for mowing steep hills.
Lawn tractors have more grip on hills and slopes than a zero turn mower.
Lawn tractors are always a better choice over zero turn mowers when you have a lawn that has lots of hills and slopes.
You can keep the front wheels under control and maintain grip while driving up a hill or slope with a lawn tractor and you can't do that very good with a zero turn.
Zero turn mowers are best when you have flat lawns and not many or any slopes or hills to mow.