I see you're participating over at KV, cool
As long as you aren't warty and green, I think you'd pass for not being a troll
While I realize from reading a few of your posts that you've put a lot of thought into what you are doing I suggest you hold off getting higher end koi for now. Imagine how you would feel to have a koi "with papers", which cost you a months mortgage payment or more, and have it up and die because something went wrong? Start off "small" and work your way up. You'd be surprised how much your taste in koi can change in just a couple of growing seasons. And read up on Quarantine. Purchasing koi from more than one source has it's own issues.
BTW, koi with papers are a gimick for the most part... and if you want to have those that are authentic then you best plan a trip to Japan

but you'd be hard pressed to find them anyways as not many breeders or dealers there have "papers" for the koi being purchased. Buyer beware. If you're looking for background on the koi you need to ask the dealer and hopefully they will be honest with you about where their koi stock comes from(who the breeders are). Don't expect that at garden centres and the local pet shop, they purchase through brokers. The best thing is to educate yourself on the many breeders, study their koi stock closely. While it appears a koi is a koi that's not the case. Like many creatures there are subtle differences in facial features, body confirmation, and skin texture(appearence), depth of colours. Most breeders specialize in a couple of varieties, like Momontaro, primarily Kohaku and Sanke is the focus.
Check out Koi-Bito(google it), the BB there is mainly focused on Japanese Koi.
Subscribing to koi topic mags is a good idea, Koi USA is pretty good. Nishikigoi International is very good. Koi-Bito is the Best I've seen yet.
There are several reputable dealers/breeders in the US and UK. Some have only high-end(show koi) but most have a variety of grades available. Where you from?
US there is Koi by Keirin, Mystic Koi, Quality Koi(breeder and dealer), Blackwater Creek, Brett's Fish Farm(breeder and dealer), Lotus Land Koi Farms(breeder and dealer), just to name a few.
Ok, done with my ramble...