Amazon FBM using Easy Ship

Hello guys, I had been selling on Amazon like about 3 years now, on Mex marketplace. About a week ago Amazon reach me out to use Easy Ship. Now in the beginning sounds good because of the shipping cost. It was very good and it will increase my profits, but now I’m having trouble with people that buy multiple products. The thing is easy ship works like this: Product price + shipping charge, Example: 100 pesos + 54 pesos= buyer pays 154 pesos I receive 154 pesos minus – Amazon fees – easy ship fees, which is 30 to 54 pesos, and then – product cost, then the result is my profit

But if the buyer buy more that 299 pesos of product they get free shipping, so the problem is here.

The 100 pesos price doesn’t get me profit, the shipping charge I get complement my price to get a profit. Some guy bought like 17 products all at 100 pesos and then I have to pay easy ship fees plus the product cost, I’m loosing money here.

And I can’t just put my price at 154 pesos, cause then Amazon will put 154 pesos + 54 pesos of shipping. My prices will be 208 pesos, and I won’t get sales cause other seller are selling at 154 pesos.

I try to just put 3 or 2 units in my inventory so people can’t but more that 299 and get free shipping, but now other guy bought several different product so, he is getting again free shipping, he bought 3 of item A, 2 of item B and 3 of item C and now he gets free shipping and it’s the same problem.

If anyone has the same situation, how did you guys solved this problem, how do you guys set prices for not to loss money?