Currently if it is in a lease that a tenant has to allow a landlord entry to a property for viewings if they put the property on the market for sale, the tenant must grant access letting in estate agents, and prospective purchasers. It isn't right during lockdowns!
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I am currently renting a house, the landlord has put it up for sale with me still as a tenant. In my lease it states I must let people in to view the property at the landlords request. They are demanding I allow people in often with there parents and the estate agent all at the same time.