in the current climate anavar is very expensive to make, if we are talking about price of oxandralone powder on the black market (where UG labs are getting it) .
now, if we are talking about the price to a chemist to synthesize oxandralone... well i have no idea, but it probably is quite cheap. the expense would be in the time you must take to study the way to make it, and also probably the chemicals and equipment necessary for the production.