Mei Chi Liquor

So Mei Chi Liquor on Flatbush at 8th avenue has Cristalino brut (google it - if you've done any reading about wine, this cava is extremely highly rated, both in and out of its price point) for $7.99 a bottle. they also have free delivery. that is a great price for a bubbly of that quality and I'm really happy I popped into this store and found it. their brut rose is also VERY good. crisp and smooth.
the liquor store's phone number is 718-622-1403.
I didn't explore the rest of their wine selection, and their other bubbly prices were on par with plaza and love's liquor stores (if you're a Freixenet fan, the liquor store on washington and bergen has it for $7.99 a bottle - about two bucks below the prices of everyone else in the nabe (it's more apple-y than Cristalino, but the brut is very drinkable - avoid the extra dry unless you like sweeter wine)).

p.s. I have no affiliation with any of these liquor stores. I just drink a lot.