Hi XXXXXX XXXXXXX;
Nice to see a fellow high desert resident come to JustAnswer for some help (I'm in Tehachapi).
Unfortunatly what you wish to do is not allowed without a permit from The City of Lancaster Building Department.
Under present regulations you are limited to a 10' x 10' storage building without having to obtain a building permit.
As for the property line it is dependant on the amount of space between the property line and any other structures. You must maintain a certain amount of clear access for emergency personel and equipment. Here in Kern County that is 15'. Im not positive about L.A. county but I believe it is the same. In other words you can build up to the property line but there must still be 15' of clear access on both sides of the structure. This also includes to your neighbors home. If their home is say 10' from the property line then you must keep the shed 5' from the property line.
Please post any other concerns here.
Best, THS
Jack of all trades Master of a few.
#1 Home Improvement Expert. Over 30 years experience in construction, and home repairs