Price Scheme for Items with known prices
k is known price, d is doubled price, b is my shop's price
k x 2 = d
d rounded to nearest even number + 1000 if number is still under 1000 mp = b

so for example a plushie from the plushie machine would be
250 x 2 = 500 + 1000 = 1500

Limited/Restricted Taxes

Limited Tax: 25%
Restricted Tax: 50%

ex. Limited Plushie would be 250 x 2 = 500 + 1000 = 1500
1500 x 25% = 375
1500 + 375 = 1875

Unknown Item Price Scheme

check price -> round down to nearest least complicated number

ex. item priced at 459999 would be rounded down to 450000
(ps. unknown price items will occasionally be price adjusted to be cheaper)