We moved from a single dedicated server to a colo 5 years ago and we've never looked back. It's saved us a lot of money. We started with 2 lonely servers in 24U and now we've got 9 servers, a couple routers, a couple switches, and some other stuff in there.
Here are my tips for people that are considering a colo. These are really all about working comfortably within a confined space (a half rack or smaller)
* 10U is not that much. Don't buy space that you aren't going to need but compare prices and find out about options for expansion. Space isn't expensive but you might have trouble buying space that isn't bundled with power.
* Keep your wiring organized. Don't say "I'll fix that later".
* This goes hand in hand with the previous: If everything has redundant power, are you going to run out of outlets before you fill your space? Consider installing a metered PDU (or PDUs) before you add any machines
Also, like justauser said, get a complete price list. Sucks to grow and find out that you are going to get hosed on cross connects or extra power or something like that.
Here are my tips for people that are considering a colo. These are really all about working comfortably within a confined space (a half rack or smaller)
* 10U is not that much. Don't buy space that you aren't going to need but compare prices and find out about options for expansion. Space isn't expensive but you might have trouble buying space that isn't bundled with power.
* Keep your wiring organized. Don't say "I'll fix that later".
* This goes hand in hand with the previous: If everything has redundant power, are you going to run out of outlets before you fill your space? Consider installing a metered PDU (or PDUs) before you add any machines
* You probably don't need 2U servers. The 1Us that I currently buy have 2 CPUs, 10 x 2.5" drives (also handy for SSD) and redundant power: http://www.supermicro.com/products/system/1U/1027/SYS-1027R-...
Also, like justauser said, get a complete price list. Sucks to grow and find out that you are going to get hosed on cross connects or extra power or something like that.