Does it make sense to find clients on the WEB using Yandex Direct? Anyone had experience of remote clients?

The direct meaning is, of course, to sell there, but it is a mass channel with very low efficiency due to the fact that there all the climb (prices there for a long time inflated, and the return is one of the lowest).
I remember 10 years ago, selling "website development" through an Internet search -> and this scheme gave the LOWEST impact of all of the schemas used, I would even say ridiculous, for example having to search the top on some popular request type "creation of sites in Syktyvkar" a website, still sell out there will be microscopic.
People more efficiently to catch up to the moment of occurrence of a need, to the moment when he wants to order a website, he already knew who he would order.
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about the deposits, usually, no special problems, you can negotiate if you wish. You can also use the order to divide into larger number of stages/payments (reducing the risks).

> send the Deposit is not known who over the Internet
to do this, there is such a thing as legal.person and the contract

> Does it make sense to advertise on Yandex for website development? Were there real customers?
if you are an Agency and the price tag on the attraction will cover the costs of advertising, why not. Do you think agencies working yet.