Legal Question in Business Law in California

Re: Maximum property storage fees

My recommendations are that you charge a fee that is reasonable as to your inconvenience and/or expense. Should the owner of this item contest the charge, you might lose if the charge is unreasonable. Advising him a charge will be added for each day it remains in your possession may convince him/her to get it moved.

Re: Maximum property storage fees

Other factors to consider are (1) how the item got there in the first place. Did it come into your physical custody through your voluntary act of some kind, or was your initial custody involuntary? (2) If voluntary, was your initial custody with the intent of making a profit based on the item (e.g. you were going to repair it for a fee, or you were going to sell in on a consignment basis for a commission), or were you just keeping it as a kind of favor, with no profit motive? (3) Was the owner there as your tenant or a prior co-owner of the premises? The answers to these questions may affect the reasonableness of any storage fee.

You should notify the property owner of any proposed fee as soon as possible.

You should be careful that accumulated fees do not approach or exceed the fair market value of the item. You could possibly be charged with the tort of "conversion" -- the civil version of theft -- if you wrongfully allowed a confiscatory storage charge to accrue.