Aged domains? What's the deal with them, not like they have any extra value because they are old or something like this. Old domain without traffic is same as brand new one. Please explain benefit of those you are selling?
Googles gives a slightly higher score to aged domains for search rankings.
No it doesn't, sorry but that's just BS.
Look up SEO and Matt Cutts and domains. Things like the extension, age of the domain, whether you use https, etc. all matter to a certain extent but they change the algorithms all the time so it is hard to say how much. It has been well known for years that aged domain score slightly higher. .com scored higher over .info, etc. The effect is small so for big sites it won't matter. See
http://www.theshortcutts.com/
