Where are the cheapest places to rent, no more than 40 mins commute to central london?

Obviously the cheaper places are less desirable but try places such as Luton, High Wycombe to the north or Lewisham and Croydon to the south and east if you want cheap. If you want a little closer then perhaps New Cross, it is an improving area since artists have taken to live there being near Goldsmiths college. Another good idea is to look at where you need to get to, find the transport links and work out. From Oxford st you have the central, Bakerloo and Victoria lines. Central to the west North Acton and beyond to Perivale are cheap, to the east try Leyton. Bakerloo to the south Elephant & Castle is cheap and although not really the best area is improving and is surprisingly close to central London, you can walk to the South Bank in 10 minutes. Bakerloo to the north and you get to cheap areas such as Wembley. Victoria line to the south is expensive but to the north east gets cheap, I’d avoid much of it like Tottenham but Blackhorse Rd near Walthamstow isn’t too bad. It is working class and Farley poor but not actually that bad, much quitter than Walthamstow central. It is actually pretty quiet and your money goes a long way. I lived there for a year and shared a house with one friend and we had loads of space, two large bedrooms, sitting room, dining room, conservatory and decent garden all for £1,000 a month, I had three times the space I have now in a better area.

Sydenham Penge Beckenham Bromley Harrow Surbiton Twickenham Watford Ruislip Wembley Edgware All have good frequent rail or Undrground links into central London

you can rent a nice flat in purfleet for £650 a month and its 25 minutes on the C2C train to fenchurch street.

Sounds like Se3 or Greenwich would suit you Hard to say as that based on just you and hubby :P