2007 Honda City starting problem

Hi guys. Im facin d starting problem of my honda city 2007 gxi. Dis is realy disgustin because dis is nt d first tym ever since im facing dis prob.10days back for d first tym I faced dis prob, so local mechanic advised to recharge d battery as it got discharged.I recharged it nd placed it, it worked fine. Aftr 2 days I faced d same prob. Again I recharged d battery, dis tym he disconectd my central lockin system as he found may b due to it battery is gettin discharged. Again recharged it nd placed, wrkd fine again. Same prob aftr 2 days again, dis tym he disconnectd even music system. Wrkd fine. Again nw same prob. Dis tym I din go to him because hel disconect someothr part nd latr d same prob persists. So plz guys give me some solution for dis, fedup vth des mechanics!