That website is very skimpy. You don't know that he even edited the specific books he shows, and you don't know that he wouldn't outsource your project to a staff member or freelancer. Or that it's even the real guy, not some imposter with the same name.
I would be wary of any agent that told me to pay for a pricey editing. Either your book is good enough for a publisher's editor to tweak for free (at no charge to you) or it isn't. Who is this agent who told you to do this, anyhow?
Another thing -the word "edit" is thrown around a lot, so much that it means different things to different people. If your book is so lacking right now that it needs an expensive "edit," what it probably really needs is a REWRITE, which you should be doing yourself, perhaps under the guidance of a teacher at a community college or something. To me, "edit" means fixing grammar and spelling. Structural fixes are not "edits," they are rewrites.