2001 BMW 325i instrument cluster going bad

My battery went bad on my 2001 BMW 325i I went about another battery and put it in an instrument cluster would come back on I let it sit for a couple hours and it finally came back on I was told my instrument cluster is going bad three to four weeks later my alternator went out I bought another one instrument cluster did the same thing when come back on let it sit finally came back on my display window it's damn like it's going out once I cut the car off and comes back bright my temperature Gage light is about  to go out my DSC and brake light is yellow it's no how much would it be to get that fixed?? If you can email me back and let me know I sure appreciate it thanks