I am not expert and I rarely drink but I called BS on my friend a couple of months ago and Pepsi challenged him that he could tell the difference between Korbel @ $9 a bottle and Moet White Star @ $35. He failed as he could not say one was better than the other. I know 35 is still "cheap" but thats a 4:1 bottle ratio for a party setting. Any opinions?
The Tasting Room is having an at-cost Champagne sale right now. It's ridiculous the prices you can get these bottles at, i.e. Heidsick Monople Blue-Top for under $30. For cheaper stuff I'd go with Roederer Estate (Cristal's California version) for like $13.50. I bought a case for like $175 after tax. It's delicious. Also, Cava (Spanish bubbly) is really hot right now, and usually around $10.
In Cava, I like a well-chilled bottle of Segura Viudas and Paul Cheneau . I'm not a connoisseur, but those taste good to me, and I prefer it cold.
I don't drink and know diddly about alcohol, but I've read where Costco often has "easter eggs" in their wine department. By this I mean every so often they'll sell a bottle of wine that normally runs $50-$60 or so (or maybe more, I forget) for something like $15-$20. I think they sometimes do this in other departments as well.
Champagne (as in, from Champagne, France) is generally pretty "expensive." Try a dry Prosecco from Italy. Or, what I prefer, is a Cava from Spain. I highly recommend Nadal Avinyo Cava. Cheers.