Throughout Sealed-System Specs, the 50 Percent Repair Cost Threshold Determines Appliance Replacement Decisions
https://www.slideserve.com/arthusobkn/cost-ratio-data-shows-when-repair-expenses-signal-appliance-replacement-time
The 50 rule for appliance repair states that when repair costs exceed 50 percent of the appliance's replacement price, replacement typically becomes the better choice