Thank you all for replying. The landlord is an Accountant, so I think cash payments more likely has to do with tax.
On another note, do you think 825pcm is a good price for a 1 bed flat in bounds green? It's close to the tube, relatively new establishment, gated entrance to the block,ground floor, quiet neighborhood, nearby shopping center in wood green.
GMap location if significant http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=N22+7as,+United+Kingdom&aq=&sll=51.58786,-0.169381&sspn=0.043835,0.154324&g=N2+7as,+United+Kingdom&ie=UTF8&hq=&hnear=London+N22+7AS,+United+Kingdom&ll=51.601186,-0.121043&spn=0.005478,0.01929&z=16
appreciate your thoughts.