Hi @Jayant Kaul That's a million dollar question literally! So far in our experience, building a list based on the revenue has always been unreliable.
• If you are generating a list of enterprise companies which are publicly listed, you can take their actual revenues from various sources.
• If you are generating a smaller companies list, you might be able to take only a projection.
• Funding is something you can consider if you are looking at Start-ups.
• You could try Apollo in case of a projection of revenue or funding details.