Every task carries what skipping it costs
A maintenance list is a list of chores, and chores lose to everything. What changes the arithmetic is the second column: the choked filter that ices the coil and takes the blower with it, the gutter that spends three winters putting a roof's worth of water against the foundation, the tank whose solids reach a drainfield that costs five figures to replace.
So every task on the schedule carries the reason it matters and the typical bill on the other side of it, and the year's list adds those up into one number. That number is the product. It is what turns "I should get to that" into a Saturday morning, and it is the only thing in this category that has ever reliably done so.
The second column