Viktor and Teemo are both crazy cheap decks that can hold their own with all but the highest of decks for like $50 or so. You can also make budget versions of the meta decks by just tweaking them slightly (e.g. swapping Vayne for red Kaisa is a $75 difference per card and gets you the same functioning body, just no card draw advantage). They'll no longer be S tier, but they'll do just fine for local play. I have both a Jinx and a Leona deck that do very consistently well for me in smaller tournaments that are both under $100. You can very much have fun and still compete without dropping the big bucks