Landlord Tenant

Is a landlord responsible for the pest control bill for rodent/varment infestation in the dwelling?
Is a landlord responsible for the pest control bill for rodent/varment infestation in the dwelling? (The tenant notified the landlord and gave him/her one month to fix the problem. The landlord never did anything about it, therefore, forcing the tenant to hire a pest control company.)
What is the definition of "common area maintenance" items which may be charged back to tenants?
Does the Delaware code re commercial leases contain a definition of allowable "common area maintenance" items which may be proportionately charged back to a tenant by a landlord?
If I just brought an apartment complex do I have to keep the old tenants?
If I just brought an apartment complex do I have to keep the old tenants? Can I raise their rent?
If it is not indicated in lease, do you have to give landlord a set of keys to your business?
If it is not indicated in lease, do you have to give landlord a set of keys to your business. Also, can the landlord come and go as they please without giving notice to tenant to come in and inspect property.
Does recording a lease protect a tenant if the building is turned over to new ownership?
Does recording a lease protect a tenant if the building is turned over to new ownership. We have a two year lease and would to know if building is sold does new owner have right to boot us out before end of lease. Also, the contract of sale will not indicate that the new owner will have to honor balance of lease.