Reviewing our brand for the year, the amount of fees we get from amazon is just brutal at this point. Here's a realisitic P&L if you want to sell on amazon.

46% fixed fees from amazon.
20% to ads (plan down to 15% this year)

13% operating margin. 66% to amazon.

Then add to that your actual overhead. Salaries, storage, insurance, software, etc...

Cash flow wise we added most of our income this year right back into expanding inventory (brand is grew a lot over 18 months) plus amazon's holdback is 6 figures at this point.

The float you need on a physical products business is no joke.