Vault Tek built 122 Vaults. Not all sealed underground environments were Vault Tek Vaults and most aren't even called Vaults. Most of the non-Vault Tek sites are military or civilian government but there are also some Family "Vaults".
Some of the non-Vault Tek not-called-vaults Vaults we have been exposed to include:
Mariposa Military Base
Lost Hills Bunker
Hidden Valley Bunker
Raven Rock (based on a real world military bunker called Site-R which is located in a place most of the people in these forums have never heard of called Raven Rock)
There is a private vault under the Sierra Madre casino.
Those aren't even all the ones we know about. There should be Military "Vaults" and Government "Vaults" and Company "Vaults" and Family "Vaults" all over the place. Vault Tek is probably the only ones that were building "Vaults" that were designed to use the residents as lab rats, but it is a certainty that others were building "Vaults".