amazon fba cost

Hello, I am opening an e-commerce for my jam, pickles, and extra virgin olive oil business. I would like to get on Amazon, apart from the issue of creating product pages, the limit I see to growth is to get into FBA and prime. From what I see from the rates, to make an FBA with one of my products, a 212g glass jar of jam, which including the jar comes to a total of 380g, the selling cost is 6-7 euros, it costs me to produce it from 2.30 to 3.00, but Amazon FBA asks for 4.42 for storage in Italy and shipping in Europe, which maybe in Germany can even be sold at 10 and in the end, the problem does not exist, but looking at some competitors, they sell those industrial ones at 2.50 so going to lose between FBA and product cost, they will have particular agreements or are there other ways to make an FBA less expensive?

Hi I am also an FBA seller, however I also do not know how some sellers achieve such small costs. Surely they are not paying FBA fees as they would be at a loss. If you find an answer to your question please let me know