In my opinion the OP can charge whatever he likes. That is called Free Market like it or not. If there would be a maximum price set by some regulatory institution it would not be a free market anymore (this is my discovery of the century). In free market an equilibrium price is found, eventually the OP will have to lower his prices otherwise he will not get anymore business.

Will buy from OP if bitcoins are needed! Since he offers to help set everything up I am willing to pay the well deserved premium. (differentiation)

gracias