Arbitrage Opportunities: How to Capture Price Differences Between CEX and DEX?

Recently, I've noticed frequent price discrepancies between CEX and DEX, and I would like to ask how to engage in arbitrage.

My questions are:

1. What price difference is worth arbitraging?
2. How much capital is needed?
3. What tools can be used to monitor price differences?
4. How should gas fees be factored into costs?

I hope experienced individuals can share their insights!