I have tenants storing metal for sale, beat up in-door furniture, toys, bikes, a grill all around the ground of the property (front, side, backyard). In what method and how long do I have to give them before disposing of these items?
What does the lease state as to how the property/yard can be used and how it should be maintained? If it's a lease violation, you can send them a Notice To Quit and demand it be cleaned up and removed immediately in order to avoid eviction proceedings - which are not part of the moratorium. What you have to be careful about is determining whether you have the right to demand removal and that's where the lease comes in. Otherwise you don't have the right to throw away their personal possessions. If the lease has ended and they have abandoned the property, every state has laws on how it has to be handled and notice to be given.
They sound "entertaining" for sure...find that covenant in the lease to give you some fire power and then make a formal and strong demand. (And, I wouldn't give them much time - 7 to 10 days max probably less) or it will never happen).
Fingers crossed for you...
They are in violation of the property maintenance code. Your lease should address code violations. The tenant has control of the property so therefore they are responsible. See below.
The owner of the premises shall maintain the structures and exterior property in compliance with these requirements, except as otherwise provided for in this code. A person shall not occupy as owner-occupant or permit another person to occupy premises that are not in a sanitary and safe condition and that do not comply with the requirements of this chapter. Occupants of a dwelling unit, rooming unit or housekeeping unit are responsible for keeping in a clean, sanitary and safe condition that part of the dwelling unit, rooming unit, housekeeping unit or premises which they occupy and control.
I wouldn't give them anytime. I would send a notice to remediate this in 21 days or vacate the premises. It's never a good sign that your tenant is a hoarder.