I am aware of the question House Price Data in UK by LSOA.
While it does have some excellent answers, their granularity is postcode.
That is actually good enough for me, but I need to be able to correlate each house sale price with a latitude & longitude (a bonus for additional data, such as number of rooms/square footage, garage, detached, semi-detached, flats, etc - but I really only need price and lat/long).
I started with the governments data for last month's house sales, of which there were more than 65,000 in the UK in September.
I tried using an Open Street Map NOMI API to get lat/long from post code. But, 65k requests blew the 30 second limit on a PHP script.I suppose that I could pause between requests, or offload that part to the client side & build my map gradually, but that might take 5 or 10 minutes :-( and that's only for a single month.
So, short story long, I am looking for a data source that has already done the conversion and can provide me with sale price + lat/long for UK house sales, preferably a month at a time.