I've just run a virtual pedigree inputing our breeder's sire and dam
http://cockerspanieldatabase.info/pedigreevir.phpand my potential pup has a COI of 14.97% over 10 generations.
I've read this topic with interest
http://www.cockersonline.co.uk/discuss/index.php?topic=44026.0 but I haven't found anything on COL that answers the question - would you be worried about a borderline number of 15% or not?
Most info I've seen views 10-15% as ok but not ideal, 15-20% not great (although obviously not as bad as 25%).
Given our past history of losing a pup with kidney failure, I am doing all I can to ensure a healthy dog. Both dam and sire are cleared on DNA checks so we're ok on that front but together there does seem to be a higher level of inbreeding - which I gather could lead to other (perhaps only minor) health problems.
The breeder has been personally recommended to me by someone very involved in Cocker Spaniel Society who is reputable and trustworthy. The sire and dam have COI of 6% and 7% but mated together - they are both gold colour, the inbreeding rises. I will have the chance to meet both parent dogs when I visit so will look at temperament etc.
All in all, I feel comfortable with the breeder and the history of the sire is particularly good, and I'm delighted to have found a choice of gold pups not a million miles away from home.
It is such a minefield - the more I learn, the more questions I have.