How do you figure that? You can rent the exact same server as a dedicated server. The difference is, you have no capital outlay up front, you don't need to ship and rack it or replace broken parts and there is only a month-to-month commitment.
I've never had problems ordering custom hardware from my dedicated server providers. At worst, all I've had to do is pay a one-time fee for a particular component. SSDs have never been a problem. Neither has any Intel CPU.
It of course depends on your provider.
Rent vs buy depends a lot on the circumstances. Maybe if your requirements don't change and you don't upgrade your server hardware it's cheaper in the long run to buy. However, when I've kept a server for more than a year, I've always been able to negotiate a discount.
You didn't post your config, so I can't tell how exotic your requirements are.
