How to Monitor Cash Flow for E-Commerce Businesses

What key metrics should e-commerce businesses be monitoring? What is it that they should be looking at on a daily or weekly basis? So the easiest one, first and foremost, is net cash flow. The next thing I'd like to look at is sort of operating cash flow. It's just a measure of if you pay your supplier today, how long is it going to take you to collect the cash from your customers? And so I would love people to look at that number.