Bought a car from we buy cars , battery has to be jumped to start the car cause car couldn't move it was dead flat , after that drove home next morning drove to the mall when I had to drive back home car couldn't start , had to seek for help so that I can

Bought a car from we buy cars , battery has to be jumped to start the car cause car couldn't move it was dead flat , after that drove home next morning drove to the mall when I had to drive back home car couldn't start , had to seek for help so that I can jump the battery, not s**** yet if the exact problem is the battery, Alternator ,starter or electric issue cause the right back indicator also doesn't work, now the car is standing at home can't drive doesn't start , waiting for mechanic not to fix it but to diagnose over the weekend so that we can detect the issue. Any guarantees since the car has been bought recently?