Opening Scarlet & Violet 3 Pack Blister [Dondozo] returns about $11.76 in card value against its $30.95 price — roughly $0.38 back per dollar spent. On current prices, you lose money on average by opening it.
See every card and pull rate in Scarlet & Violet Base Set
How expected value is calculated — card value only, from published pull rates and daily market prices.