Use higher/more internal DECIMAL PRECISION when calculating GRADUATED prices? | Shopware 5

Hello everyone, 

we have certain products that have graduated prices.
That means: the more a customer buys the cheaper one piece of what he buys should be.

So far so good, the problem i’m having which is problem X is that we have fixed gross prices for certain amounts.
so we have 10, 20, 30, 40, 50 … pieces.
Lets say 30 pieces should cost exactly 173.48 € gross.

In shopware i can only specify graduated prices
with netprice
on one piece

so i would need to remove the VAT from my gross 173.48€
173.48 / 119 * 100 = 145.781512605
and now i need to have the price of only one product.
145.781512605 / 30 = 4.8593837535

I can enter a price with higher decimal precision than 2 in the database, so i did that!
But shopware still seems to calculate with a rounded price of one piece, the price that will also be shown to the user.

so instead of calculating internally with 4.8593837535 it calculates with 4.86
4.86€ * 30 = 145.8€ net
adding VAT 145.8€ * 1,19 = 173.502€

so i end up with 173.50 altough it should be 173.48
those are only 2 cents, but these amounts can grow to huge numbers.

Here comes Problem Y with which i thought to solve Problem X, increase internacl decimal precision in calculations.
My question to Problem Y, where can i do so?

And if there is a better solution for Problem X what would it be?

Thank you for reading and any help !! <3