The kohler always had a very good reputation. Check consumer reports for what they say.
check your local classifieds; check with a dealer who takes trade-ins. Check with an on-line site such as Craigslist or the auction sites for completed sales.
2) Increasing returns it cost $60 per mower when making either 300 or 400 mowers, but only cost $48 per mower when making 500. Assuming she charges the same price for mowers, her returns are greater (increase) when she produces 500 compared to 300 or...