Landlord sent in contractors to see about new sink unit but they complained to landlord kitchen was dirty and untidy and landlord wants to come in. I understand landlord can be liable for tresspass against tenant. Any case law on this point would help.also I am waiting for data of allegation before allowing anyone in as I have doubts about purpose of contractors to begin with. thanks

First I've moved this to Real Estate law where it belongs.

Second, Most leases allow a landlord to enter the premises for repairs. So there should be no issue of trespass. You need to read the lease.

In absence of a lease, most state laws allow the landlord to enter the premises with reasonable notice... usually 24 hours... with or without your permission.