The Design and Organization of Data Centers/Location

Co-locate

 * telephone company central offices
 * carrier hotels

Cost
Shop around to compare prices. Many co-location centers give initially inflated prices.

Suitability

 * Proximity to multiple major network backbones.
 * Proximity to customers if that is a consideration.
 * Distance to central office

Transportation

 * Proximity to public transportation
 * Proximity to highways

Availability of emergency services

 * fire insurance category

Safety from water damage
HVAC can fail in such a way that water comes out. Look out for pipes, vents, and ducts above your equipment. Air conditioners can freeze up and then thaw, water heaters can fail, ventilation ducts can pack with snow, toilets can overflow, etc. The building may be in a flood zone - does the insurance cover the damage? How long will it take to file the claim? Document who you must contact before the disaster happens.

Natural hazards

 * Wildfires
 * Hurricanes
 * Tornados
 * Earthquake
 * Mudslide
 * Tsunami

etc.

Manmade hazards

 * Proximity of pollution sources
 * Transportation-related risks
 * Risk of crime, violence, terrorism, etc.