Short voice cellular numbers

The idea of ​​a new project was born recently and I am trying to figure out the costs. The most expensive, perhaps, is the payment of a short voice cellular number (such as 1234). But no specific information on this topic could be found, Beeline / MTS / Megaphone are also silent on the request for such a service.
Room needs a local, within the same city; although further expansion is possible.
Who faced, worked with a similar, please tell us? How, what, where, how much?

PS Number does not imply receiving money from the callers, i.e. for callers should be free. It is needed to promptly give them some data.