In California, a security deposit for residential property unfurnished, the security deposit may equal 2 times the rent. If furnished, the landlord may charge up to 3 times the rent.
In California, there is no such thing as a “non-refundable” security deposit. No matter what it’s called—a key deposit, cleaning fee, move-in fee, closing costs, last month’s rent, etc.—all money you pay in addition to your first month’s rent is refundable. Since “nonrefundable” deposits are illegal, don’t worry if your rental agreement includes a section about a “nonrefundable” deposit. This section will not be valid even if you have signed the rental contract
or agreed to it.
If a tenant damages the property, the landlord can deduct the cost of fixing it from the security deposit. But if the tenant returns the rental in substantially the same condition in which it was rented (less normal wear and tear), the landlord must return the deposit. A landlord can't make tenants pay for painting, new carpets or curtains, unless there was serious damage. The landlord is allowed to deduct the cost of cleaning if necessary to put the unit back to the same level of cleanliness it was in at the time the property was leased (less reasonable wear and tear).
Within 2 weeks of the tenant's move-out date, the landlord must advise the tenant, in writing, of the right to be present at a walk-through with the landlord. The purpose of the inspection is to allow the tenant an opportunity to repair damage pointed out by the landlord.
So in summary, if there is a stain that won't come out and it is large enough to not be considered normal wear and tear, then you would have to pay to repair that from your deposit.