98 blazer not starting

I have been struggling with this problem for the past couple of weeks. The darn engine will not start. If I do not run it for 3-4 days, the car battery dies. I am stuck to deal with calling AAA and having them jump me. I have taken it to the shop twice now, the they do not know what the problem is. I have gone through 3 batteries in the past 3 months. I have taken out an after market alarm and and amplifyier, that i had installed 5 years ago, and have gone now through 2 batteries since then. All instruments are turned off everytime i shut the car down.


Has anyone had this problem, and how can i fix it to sell it.