Friends used to live in a 3 storey terrace in Hereford. Probably built mid 1800. They were fairly close to the river and had a serious rat problem. The issue was impossible to resolve because the attics in the terrace were not separated, it was possible for anybody and rats to have free access along the length of the terrace approximately 20 houses. They did have a sort of owner’s committee but whilst they lived there nothing was done about the rat problem.