Personal Finance

There are cards out there like the “Fold” card that will give back up to 1.5% in BTC for ACH transactions, but that’s contingent on you spending a lot on other transactions and the card also has a $100 annual fee.

Look up "there ain't no such thing as a free lunch" from Robert Heinlein.

Generally speaking, if you're getting given something, there is some sort of mechanism by which the card issuer is going to get more than the thing they are giving you. Otherwise they wouldn't do it. Sometimes they will offer incentives where you can actually make some small profit, because they want to bootstrap the usage of some new service by bribing people to use it for their real-world big transactions. But that will generally stop as soon as the new thing is established. Sometime they will give you a piece of some cut that they're getting (they charge 3% to the merchant as a processing fee, then they give you 1% in rewards as your cut, so you'll use the card more and their 3% will be higher). But, in general, you won't really be able to beat the house by more than a miniscule amount.

They're looking to bring money in, not give it away to you.

Credit cards pay out rewards using money they charge merchants on the transaction. The cards discourage merchants from offering a discount for people who pay in less expensive ways, but if you ask you can often get a discount for cash. Typically the cards charge merchants 3% and give you back 2%. Cards are worth it to a merchants such as gas stations but usually not worth it for companies accepting rent. If you rent from an individual, you might get a discount for giving them cash or check, but a company with hundreds of units probably prefers paying the small ACH fees to avoid dealing with physical payments.

ACH?

If your paying rent and such from a checking account. I recommend a Fidelity Cash Management account. It’s a checking account with an interest rate (currently at 2.19%), so the money sitting in there before your rent payment happens it’s making (some) money.

We pay many bills via credit cards, which we then pay in full every month. The credit cards offer something like 2% cash back that can be applied to pay down the balance of the card at some point in the future.

It's not much, but it's essentially giving us a 2% break on the bill. Of course if you carry a balance, the interest will far outweigh any gain. So you have to be disciplined and careful. The cards we have do not have an annual fee, either.

The card company still does it even without charging us interest because they make money on the transaction - they charge the vendor a fee.