" houses that eventually end up in the hands of Rachman type owners who fill them up with people getting there extortionate rent paid by the Lewisham council "

Well it gets even more brilliant (NOT!!!) than that.

Because a few years ago, Lewisham council was giving landlords a grant of £15,000 per unit to bring rental properties onto the market - so, potentially, the hideous conversion of just one these houses containing 6 units each could have put £90,000 the landlord's way even before he started raching-in (raking-in a-la Rachmann) that ridiculous £69,120 per annum!

Although there didn't seem to be any evidence of anti social behaviour emanating from those 3 6-bedders, which would probably have been converted under Permitted Development, thankfully, IMO, Lewisham is bringing in a new rule whereby these HMOs (Houses in Multiple Occupation) will need full Planning Permission, which will be refused if it's likely that neighbouring amenity will be adversely affected.