Yesterday, I visited the Thepprasit night market (google map is your friend).
I highly recommend it for those looking for cheap prices.
It's huge and probably 2 or 3 times cheaper that what you'll find in the city center.
A nice slice of pizza is 20thb, a good kebab starts 80thb, Mo ping is 10thb, spicy spaghetti with bacon or sausages just 50thb, etc...
And it's very good. Much better than what I had at Tree Town or Wat Chai Mongkhon market.
For those looking for clothes, many good deals as well (not as good as Lazada I suppose but this experience is different altogether).
Many things are priced around 100-150thb.
Had a very nice time there.
Anyway, hope this helps.