FYI: If you tie your account to an xbox/microsoft account, you can use the rewards points gained through the microsoft rewards program to easily pay for the Interknot membership/City Fund every month (good for dirt-poor people or if you don't want to spend "your" money on a gacha game)
1.)Make a microsoft account to join the rewards program 2.)Earn points through doing their tasks 3.)Connect your Hoyoverse and Microsoft Account 4.)Redeem the rewards points for Xbox gift cards (You can save on points if you have an xbox, as you can do the autoredeem for $10 USD/8750 points instead of the normal $10/10000 points) *Be careful with step 4, you have to spend the credit within 90 days or else it expires 5.)Use your microsoft balance to either pay for the Interknot membership as an "add-on" in the microsoft store, or go in game either through an Xbox or through streaming to be able to purchase the city fund and other bundles (Only direct monochrome purchases and the interknot membership appear to be available through the microsoft store itself)
All of this is from an American perspective of course, the microsoft rewards points program is different in other countries. Your mileage may vary. Now, you too can be a paypig guilt-free!
If you're playing this game, you're probably already used to doing little tasks for little rewards every day. If you max out ABSOLUTELY every task every day, it's possible to make $15+ a month which is enough to pay for an interknot membership and the city fund with a little change. May be able to even top up here and there, depending on whether you want the city fund or not, you little gambling addict!