A landlord must give reasonable notice of an inspection visit or have a VERY good reason to enter without an appointment - maybe if he smelled fire, saw leaking water or something similar.
Your local authority may have a 'Tenancy relations officer' who can help
Emergency only.Otherwise he needs to make an appointment with you at a reasonable time of day and that suits YOU. Obviously of you keep saying that all his appointment times are not covenient then you are been unreasonable which is no good for anyone. I rent a flat out and I tell any new tennants that as long as they are reasonable and pay the rent on time then they can treat it as their own.