Problem with Wifi Connectivity in multiple places

I have a MacBook Pro and I am currently running OS X Yosemite 10.10.3 and I am having trouble connecting to a Wifi signal and when I can connect It will disconnected randomly. This problem happens to me regardless of the router I am trying to connect to (Home, office, etc.), other people don't have an issues connecting their devices, and I assure you that I am imputing the correct passwords. I have zapped the PRAM, Deleted the networks from the network preferences and reentered them, I have deleted "WiFi" from the list of internet connection methods ( along side Ethernet, FireWire, etc.) and added it again, and after I exhausted every troubleshoot I could think of I finally just erased my hard drive and reinstalled OS X. Long story short, I am still experiencing the same problem. I can however connect with a Ethernet cable but that doesn't help me. Is there any other thing that I can do to fix this problem without actually bringing it in the Genius Bar? or is that the only thing I can do?