Evaluating B2B Data Vendors: Seeking Recommendations and Insights

Hi everyone, I’m evaluating B2B data vendors and currently looking at Nimble, Apollo.io, Snov.io, Hunter.io, Lusha, Sales Shady and Lushaa. I need a cost‑effective provider with at least 80% data accuracy. Has anyone here used any of these? Or can you recommend other vendors that meet these criteria?