Why won't my Ipad charge?

I have an Ipad Mini 1st Generation. I plug it in and nothing happens. An hour can go by and the ipad will start to chime about every 20 seconds or so. Nothing shows up on the screen and I can leave it charging all day, and still nothing happens but the chiming. I hook it up to the laptop and the laptop recognizes it, says it's charging, but the same result. The screen is still intact, no water damage. I've taken it to three different "techs" (one of them at the apple store) and all three told me something different. One said the ipad is fried. (what does that mean?) Another told me the port needs replacing, and the last one told me the screen is bad. I've fixed a lot of my own apple devices and have found out that these ipad 1st gens are a bear to open up, risking the chance of breaking the LCD or glass. Someone please tell me what this may be so I have a better idea. I don't have a lot of money so I'm going to have to fix it myself. The apple store was so "willing" to sell me another one. Thanks, I don't see why I should have to buy a new one when this one could be fixed. Please help...