Hi I am not sure who Pilcher is that you have reported this issue too. Anyway, our property manager is off ill at the moment and has been very busy with all the year end stuff. When he is back I will speak to him and find out what the recommendation of the pest controller is ( I believe we use EBS). The bottom line is that the space behind the walls inside the flats is in fact not common area and is the responsibility of the Tenant. That said it is my opinion that an issue like this will eventual effect all unless its dealt with. It also appears as if there is some seasonality associated with it as it was when the weather turned colder last year that the reports started to come in. As far as I am aware it seems as if its just blocks 6 and 7 that are effected. When I have some further information I shall provide it.