I know you arent there yet, but anything 240+ isnt even tradeable. The difficulty to do these things alone also spirals out of control so you have to party and split the income. Therefor silver farming is better done solo somewhere lower.
Basic stuff like demon prison grind on your own yields 300k per hour in raw silver and there is more stuff you can do. Istoria aswell yields good results + drops you can sell.
Worldboss farming yields good results aswell if you can e.g. do dullahan stuff. Especially overleved since you have access to a lot of them - but that is something guilds do on femidian at least.
Other people have created 4+ lvl 90 chars and just bossrush the dungeon for arde dagger which can also yield a mil in “hours” (not counting the creation of said twink here since that is the investment). A bossrush run takes like 5 minutes tops you cycle all your chars…