I just moved into a building with three apartments, all of which split an internet subscription. There is only one router, however, in one of the other apartments. For security/privacy purposes, I'd like to set up some way to prevent my neighbors on the same network from viewing or accessing any of my online information.
I have an old router with me, which I'm hoping to use as a wireless extender. I already know it's compatible with DD-WRT, so I'm fairly certain this will work, as long as I get the MAC address from the main router. Unfortunately, I don't have physical access to the main router though, since it's in another unit of the building. If I do this, will I be able to use my router to prevent traffic from potentially being viewed by other users on the same network? And if not, what other security options would you recommend? Would a good VPN service be more effective?