I dont know what your expecting from anavar but a KG a month naturally is incredible. I think you got some wierd expectations. I'v e probably done more Anavar then anyone on here and on a good cycle I gain a maximum of 4-5 KGs. If you can still gain a KG a month naturally your not ready for steroids. Besides the whole age thing, steroids are meant to be used once you hit your natural plateau.
And you also said that you cant spend that much money on food... what you think Anavar is cheap. You can eat steak everyday for 2-3 months for the price of an anavar cycle... which is what you should be doing