You do, with 24 hours written notice, have a contractual obligation to let them come in. However, I'd suggest the appointments have to be at a mutually agreeable time, within normal working hours usually. And it's a mute point re whether you gave notice, or they did. And under what circumstances. Frankly we were given, unexpectedly and out of the blue, notice of an intention to sell the property we'd been in for over 13 years (rather than do any upgrading!). In that case I said I wasn't happy to have prospective purchasers over the property under the circumstances, although I agreed that the agents could come in to take photos etc. The owners of the property agreed to back off. This was a bit different however - most landlords would prefer to have a seemless change over, to avoid 'down time' for the property. I think everybody is entitled to 'quiet enjoyment' of the property they are renting, so if this visiting becomes disruptive then I'd say so. You might take your issues, and the Lease, to your local Citizens Advice people, who will tell you your rights.