I am a complete beginner on a very restricted budget. I am looking for an amp to go with the Yamaha RBX270 (suggested to me in a different topic). I would like to spend as absolutely little as possible without buying something so poor that it hinders my learning or joy or playing. Do you have any suggestions of what kind, how powerful, what size speaker, and how much $$ I should spend on an amp? I will be playing this in my apartment and if I stick with it and improve I would be willing to buy better equipment in a few years. Thanks for any suggestions.