Best Ways to Collect Real-Time Pricing Data for E-Commerce Platforms?

Hi everyone, I'm working on a project related to dynamic pricing optimization and need to collect real-time pricing data from e-commerce platforms (specifically, grocery and instant delivery platforms). I’d love to hear from anyone with experience in price tracking, competitive intelligence, or e-commerce data collection. What are the best methods that are both effective and compliant with platform policies Thanks in advance for your insights!