I sympathise. It is a bubble partly as London property is resilient but with a major local push from the overground. I'm in Garthorne Rd, Honor Oak. Good, well built early Edwardian terrace houses, street parking. Neighbour sold her (very nice) 3 bed a couple of weeks back. She went out on a Sat, the agencies fed through 20 prospective buyers that day, sold on the day for the asking price of £500k and I daresay she could have got more. Mind the 4 minute walk to the station (pace the overground) helped! The buyers come from North London as they can't afford to buy there......

If you're prepared to trade some walking distance from the stations you may find prices cheaper. So parts of Perry Vale or Stanstead Rd (Forest Hill / Catford borders) may be cheaper. Good luck!