Rise of the Ronin

To do this, you must have 150,000 sen (money) at the same time. Don't spend money until you get the trophy. If you never spend money, you'll only get enough from the main missions. You also earn money from selling equipment.

The required amount of regular (not silver) coins must be in your account at once. Don't disassemble equipment, clear the map, sell all the junk and don't spend money on equipment upgrades: save up very quickly. For completing some missions you will be given a gold coin (Oban), which can be sold for good money.

In the game settings, you can enable the automatic sale of equipment of a certain quality, then you won’t have to constantly run to the merchant. The trophy will make itself, since ordinary money in the game at the starting difficulty levels is not really needed.