If you're looking to bulk buy old domains with age, pr, links etc then get in touch with me. You can buy old domains from many marketplaces but if you want the best prices and the best domains, I'm happy to help out. Check my sig for website and email/PM me.
The PR Powershot tool is a good one. Checks age, Social factors Wayback archive etc. Very handy (google it... PRPowershot.com)
Godaddy auctions would be my suggestion. I have some domains listed on sedo but never received any inquiry about them yet.
Acorndomains.co.uk have an auction feature and direct sales. Domainlore.co.uk is a good auction site for .UK domains.
If you have low budget then just look at Godaddy auctions you could get domains for low prices there and if you hold good budget then look for premium domains at sedo.
At namepros is easy find good deal, particularly because that forum resembles much like this; a marketplace where people expect to pay peanuts for domains and there is always a chance to get them at that price because often times users ignore the real value of domains they are selling. For professional deals, GoDaddy, Sedo, and Moniker auctions are good options, but also Flippa because in that place there are sometimes excellent domains with content and subscribers included.
The Domain Name Reserve (www.DNReserve.com) has a wide selection of very reasonably priced aged domains going back to 1995
A UDRP checks many things among this, however where is the prof of a new purchase ? The creation day remains the same and the update date happens more than once and for reason not related with the domain purchase
I get domains for my PBN from PowerPBN.com It's a daily list of available domains with a minimum criteria (DA, PR, TrustFlow etc.) It's manually compiled and usually got about 60-100 new domains each day and most of them are great and really cheap. It's saved me freakin' hours. It's a private membership site for serious domainers but if anybody asks you just say ViralBoy sent you and you should be fine. I'm well known there but NOT an affiliate.