renovations

Tenant claiming the cost of renovations from the landlord

Q:

1. Our tenant is withholding rent at our business premises which he has vaccated, citing that he has done some renovations and wants compensation for same. Please give shariah ruling regarding this.

2. The tenant also sublets portion of the premises and collects rent. What is the shar'ee ruling on rent collected on portion subletted. We will appreciate a mutual solution regarding this issue.