I bought the first in Nov 2017 (64 reg, 4100 miles!) for £17K. Cap Clean was £19K, I don't remember what below was but it would've been more. Private seller.
Second in Jan 2018 for £16900 (15 reg, 35K miles), Cap Clean was around £16400 so overpaid a little. There were only 5 in the whole of BCA
Then in Feb 2018 there were at least 30 i3s so my next one came in at £16K (15 reg, 20K miles) which was approx £1500 under Cap Clean, again not sure what below was.
Then the killer. A 60K miler (huge miles for this car, 64 reg) for £12K with Cap Clean of over £14K. It was in retail condition too.
And the last two in March and April, £16K and £18K respectively, similar miles around 20K, both 15 reg but one much higher spec then the other. Interestingly it's the lower spec car that gets more views at the moment... Go figure...
Also I'll tell you what I bought today:
A 65 reg Abarth, 19K miles, stunning spec, black wheels, EML on, Cap Clean £8700, mine for £7900. Not quite Cap below but normally they go a fair bit above CC.