dFlashe

So I've been having troubles with this car for the last month... I'll go in chronological order. The first problem I encountered was that I needed a Jumpstart for the first time ever on December 13 car felt normal and didn't think much of it apart from a message coming on saying to service the battery charging system that went away after another start. Then my serpentine belt snapped off around December 15 I got the car towed to my house and saw what happened when inspecting it the next day. I called my dads friend who's a mechanic he helped out and installed the new belt. Car ran good for abit atleadt 200+ miles. Then on the 20th after I stopped for a stop sign I accelerated the car moved, and then stopped accelerating although you could hear the engine revving. Luckily wasn't to far from my girlfriends house. I got the car towed there and her dad helped me out inspecting the car. We saw that the serpentine belt that snapped off was spinning in circles and getting into the wheel bearing we were able to get what we believe to be all of it out just for extra preventative measures we changed the battery and battery cables. So yay I had a working car! I drove it home 30+ miles and a few more the day after. Then the day after that I had the car in my garage. I pulled it out to the front of the house before work because I forgot to put on work shoes I turned the car off ran inside, came back out and when I turned the key to the on position the car completely died on me everything electrical stopped working. And no lights came on, nothing. I got someone yo pass me cables to Jumpstart it the lights came on like normal but the car wouldn't start just a click noise. The next day my mother called a mechanic who we didn't know much. He was looking at the car with a new battery in place he believed it to be the alternator he put a new one in to no avail the car still didn't start. Then he inspected the battery and noticed it was bulging on one side, I was able to get it replaced at autozone for a new one and the next day he took a look at it and it wouldn't start still. I was working at the time. I had lost hope at this point and just wanted to junk it. He had told me that the anti theft lock kicked in so the car wasn't gonna start, that he knew someone who is good with electrical who can take a look at it, but it would be $140 just to get it looked at. I was like no thank you. When I returned home after work the next day I took a look at it. I dont know if the mechanic purposely removed the cables from the battery but they weren't connected that day. I connected thm and tightened them and viola the car started and drove normally, I drove 5 miles on it no problems at all I decided okay maybe he was trying to get money out of me but I did notice that the speedometer didn't light up but the dashboard did? I was like whatever I'll sell the car with full transparency of that I put it in my garage while listing it. Now a week later since its last start the same problem is happening where the car didn't turn on, at first it would just make the click noise then after a few more tries the same problem arose.. all the electronics dont turn on when I turn it to the on position but this time the battery light is on when I try jumpstarting it. I checked the fuses and they are all working, I checked battery terminals they're all good aswell. I hope its something small like a fusible link like in this video https://youtu.be/s7rfl51gRLA I don't have anyone to help me out to check that though. I just want and would appreciate second opinions I am in need of the money very bad if I can figure out whats wrong and sell it. Thank you!