However, this does not guarantee that the property is free of any mortgages or other liens, as the mortgage holder may have other legal remedies to enforce their rights, such as a foreclosure action.It is always advisable to thoroughly research the specific property and any liens or encumbrances on the property before participating in a tax sale, as the rules and procedures can vary by state and the specifics of each property.

If you mean suing your tenants, that wouldn't work because the court would say you have a statutory remedy already - you have the right to their security deposit to use for rent, after they vacate - and you have the eviction remedy - normally.But, the reason you can't evict right now, is because the courts are closed. 

Remediation will likely require testing and removal of a substantial amount of soil if the spill covered more than a tiny area. 

Also we had spent a lot of money remediating a mold issue a year before.

Some that do testing and remediation may not be on the up and up.

If the sanitary conditions in your unit are such that it attracts pests of any kind, and it becomes necessary for us to undergo remediation in the building, you will be held financially responsible for reasonable costs thereof, paid as additional rent.

Here is what my standard lease that I picked up from the internet and use with my rentals:(2) Repairs that Tenant will Pay Entirely: Tenant will pay Landlord or any contractor Landlorddirects Tenant to pay the entire cost to repair:(a) a condition caused by Tenant, an occupant, a member of Tenant’s family, or a guest orinvitee of Tenant (a failure to timely report an item in need of repair or the failure toproperly maintain an item may cause damage for which Tenant may be responsible);......Appears it includes failure to timely report as a cause to make tenant pay.I also have a Maintenance Addendum that I got online that includes: Immediately notify Agent of any evidence of a water leak or excessive moisture or standing waterImmediately notify Agent of the presence of mold, mildew, or similar growth in the Premises after you have attempted to remove it using common household cleaning solutions or anti-microbial productsImmediately notify Agent of any malfunction of any part of the heating, ventilation, air conditioning, plumbing, or laundry systemsImmediately notify Agent of any inoperable doors or windowsOn looking at it now, it does not state what the remediation would be if the tenant does not adhere to this. 

You'll need to give them a reasonable amount of time to remedy the problem.  

So, we tend to send a notice out regarding landscaping a couple times a year to several tenants and if they don't remedy the issue within the time frame in the letter, we send a crew out and bill the tenant.

Best practice is to always reference the term in the rental agreement that they are violating and tie it to remedies available to you by your L-T law.In your current situation, since you say the tenant is "dirt poor" and you sympathize with their situation and the storage unit is sitting empty, it may be a good idea to renegotiate the agreement.