Forum:Card buying

I have a pretty decent deck but it has no real theme or OTK in it. I just play with a few friends who I always beat so I don't want to get expensive buying crads. But i was wondering: where's the best bang for your buck when it comes to yu-gi-oh cards? what's a good deck you could make for around $20? where could I find a ("holofoil" mirror force) (( I want one for some reason) for under $5? thanks for answering my random questions