If you can pick Heston Bale up for 5K i'd say that would be a good deal
Nah look, im only new here but from my past experience with dogs you want to obviously go for one where both the bitch and sire have won races at the highest levels for your coin and have both produced other winners.
At the end of the day you are still gambling no matter what and as with any gambling you try top reduce your risk as much as possible.
Things like not going for a bitches first litter or not going for a sire that was supposed to be the next best thing had he not torn his ligaments. This industry has its snake oil salesman as do all others.
Its not a light punt and so long as you understand that there are winners and losers and dont set your expectations to high I'd say you might just be happy with the out come.
Good luck, pardon the pun!