How Do You All Manage Cost Planning for New Projects?

I’m trying to understand how different people handle their project budgeting, especially when dealing with multiple tasks and material requirements. What kind of approach do you usually follow to keep everything accurate and organized?

I’ve noticed some teams relying on online estimating services to streamline their cost breakdowns and avoid manual errors, but I’m curious whether they actually offer a noticeable improvement in real project workflows.

If anyone has tried these tools or compared them with traditional methods, I’d love to hear your experience.