Disputes over security deposits are unfortunately common, with spats over the difference between normal wear and tear (which landlords cannot charge tenants for) and damage—that’s the tenant’s responsibility. “How clean is clean” is a perennial debate. Some states, like California, specify that rentals need be returned only as clean as they were when the rental began; others require landlords and tenants to complete an inventory at the start of the tenancy, so there’s at least a chance that the rental’s initial condition will be documented.

When landlords and tenants can’t agree on proposed deductions, the matter often ends up in court, with tenants suing for the return of their deposit. Landlords who face clean-up and replacement costs that exceed the deposit may file their own lawsuits for the balance. Because the amounts involved are rarely more than a few thousand dollars, the cases go to small claims court, where litigants are limited as to how much they can sue for.

Small claims won’t do for the San Francisco landlord who rented a furnished apartment to Giants’ pitcher Tim Lincecum last year. She’s suing the ace for losses due to damaged and stolen furnishings and property, describing destroyed “bedding, doors, carpet, pillows, kitchenware, linens, furniture, household appliances, art work, decorations, patio furniture, lights, lamps, and mirrors.” The owner claims that although the lease ended on March 1, 2011, Lincecum stayed on without paying rent through mid-May, racking up unpaid rent. The total claim: a whopping $350,000.

The landlord has a lawyer; Lincecum will doubtless lawyer-up soon. If the landlord has physical evidence to substantiate her claims, especially photos, it’s hard to imagine how her tenant will evade responsibility; and proving unpaid rent is simply a matter of showing residence plus no check.

Because going to trial will be pointless, this case should and doubtless will settle, unless the landlord’s figures are so inflated that Lincecum thinks he can defeat the claims on account of greed. That, however, would still involve the spectacle of a trial, with his private life and manners up for public scrutiny. I doubt he’d relish that.

What’s the lesson for the rest of us landlords & tenants? First, as soon as the lease expires but the tenant stays on, landlords should begin eviction proceedings. Even in tenant-friendly San Francisco, these cases move quickly when the tenant alleges no defense (such as, in a nonpayment eviction, a justifiable withholding of rent when landlords fail to maintain the property). A quick trip through the courts would probably have happened here—there’s no suggestion that Lincecum had a right to stay past the lease ending date.

The take-away for tenants is easier: To avoid being charged for pre-existing damage, be sure to inventory the condition of the rental at the outset (do a walk-through with your landlord, and have both of you sign-off on what you find). And obviously, if you damage something, pay for it.