When can &quot;exact change&quot; policies be enforced? In general, "exact change" policies are legal. The Department of Treasury provides this helpful explanation: The Coinage Act of 1965, specifically Section 31 U.S.C. 5103, entitled "Legal tender," ... states: "United States coins and currency (including Federal reserve notes and circulating notes of Federal reserve banks and national banks) are legal tender for all debts, public charges, taxes, and dues." This statute means that all United States money as identified above are a valid and legal offer of payment for debts when tendered to a creditor. There is, however, no Federal statute mandating that a private business, a person or an organization must accept currency or coins as for payment for goods and/or services. Private businesses are free to develop their own policies on whether or not to accept cash unless there is a State law which says otherwise. For example, a bus line may prohibit payment of fares in pennies or dollar bills. In addition, movie theaters, convenience stores and gas stations may refuse to accept large denomination currency (usually notes above $20) as a matter of policy. But in practice doesn't this mean that "exact change" policies can only be enforced when payment is required before a good or service is provided? Because I can incur a debt in most commercial situations. E.g.: I drive into a parking garage that lists rates on a sign that also warns, "Exact change required." Later when I go to leave I am asked for exact change at the exit. I say, "Well, I don't have exact change, but I do owe you money for parking here. Federal law says I can satisfy this debt with legal tender. So start counting the pennies, or just let me out!" I go into a store that says, "No bills larger than $20 accepted." While shopping I drink a soda and eat a few snacks. I go to check out and all I have is a $100 bill. Once again I say, "All I have is this $100 bill. I am in debt to you for the food I've already consumed, and this bill is legal tender for satisfaction of that debt. Either make change or thank you for the free snack." I get in a taxi, enjoy a meal in a restaurant, etc. All of these are paid after the service has been consumed. Are they not then debts that must be discharged if I offer legal tender?
If a business literally has an &quot;exact change only&quot; policy, that can't be enforced in post-pay situations. But if they have a &quot;you are free to overpay, but we won't give you change back&quot;, that's different, especially if it's communicated from the beginning. If they tell you they don't give change, then you're taking their goods/services implicitly agreeing to their terms.
It will vary by jurisdiction. This is a complicated area of law, but usually an advertisement or a display of goods in a shop is not an "offer" (in the contract law sense of the term), but an invitation to treat (or "invitation to bargain" in the US). The "offer" is the shopper saying "I'd like one of those please" or putting the goods on the band for the till. The "acceptance" is the checkout girl saying "that'll be ..."
Is it legal to sell currency at a price lower than face value? Yes. In fact, to donate is the act of transferring for free the ownership of something. Outlawing a transaction that is less extreme than a donation would be inconsistent with the lawfulness of donations. A significant departure from the market exchange rate does not affect the validity of currency exchange. A &quot;sale&quot; of currency in terms of itself is not illegal, since the transaction can be viewed as a combination of two transactions performed instantaneously and involving the fiction of an intermediary currency. Offers of currency for less than face value also happen very often when transacting the bonds issued by a country's central bank. Any two parties can transact those bonds in secondary markets. The scenario you describe obviates redemption periods, fluctuation risks, and various formalities, but those differences are inconsequential from a legal standpoint.
Extrajudicial implies there is some weight of law behind the casino behaviors you describe. I don't think there is. For example, refusing to cash out chips could just be a management intimidation tactic to try to coerce the customer into agreeing to be "questioned." Which the customer would be under no legal obligation to do. Card counting can't be proven if the counter is not using a device of any kind. The casino can refuse to serve the customer and expel the customer but they can't unilaterally keep the customer's money by not cashing the customer's chips without a judgment. I am not an attorney. This answer is not legal advice.
According to United States federal law, 1 U.S. Code § 109 - Repeal of statutes as affecting existing liabilities: The repeal of any statute shall not have the effect to release or extinguish any penalty, forfeiture, or liability incurred under such statute, unless the repealing Act shall so expressly provide, and such statute shall be treated as still remaining in force for the purpose of sustaining any proper action or prosecution for the enforcement of such penalty, forfeiture, or liability. The expiration of a temporary statute shall not have the effect to release or extinguish any penalty, forfeiture, or liability incurred under such statute, unless the temporary statute shall so expressly provide, and such statute shall be treated as still remaining in force for the purpose of sustaining any proper action or prosecution for the enforcement of such penalty, forfeiture, or liability. So it depends on whether Congress expressly said what to do, and if they didn't say anything, it defaults to being able to still prosecute. But this only applies to federal laws, not state laws. There's also an exception to this. In United States v. Chambers, 291 U.S. 217 (1934), the Supreme Court said that a prosecution for a violation of the National Prohibition Act could not be continued. However, this was a special case, as the constitutional provision (the 18th Amendment) that allowed the act in the first place had just been repealed (by the 21st Amendment).
The issue is not enforceability per se, it is the problem of proving what you agreed to. If the landlord adds conditions that are against your interest, he would need to show that you agreed to those conditions: if you add conditions against his interest, you'd have to likewise prove agreement. Since you both have copies of the agreement, it's a matter of comparison to see if the documents are the same. Rather than voiding the earlier agreement and rewriting everything, the change can be initialed. If you were to cross out the rent and insert a lower figure, you would need proof that he agreed to this (hence, his initials on your copy). In your case, the change is apparently in your interest rather than his, so there's no realistic way that this could become an issue (that I can think of: maybe there's a clause that has to do with the move-in date and moving in early actually works against your interest, in which case he would need to prove that you agreed. The fact of moving in early is sufficient proof of agreement).
Yes. It is normal. Almost all credit card agreements are drafted in that way. Implicitly, however, changes in the credit card agreement must be prospective only and cannot alter rights that vested under prior versions of the agreement (e.g. charging a lower interest rate). A key factor is that a credit card agreement is terminable at will with respect to new transactions by either party by ceasing to make new transactions under the new terms, or ceasing to authorize further transactions under the old terms.
Generally not. Federal court uses a principle known as the enrolled bill rule -- in deference to the coequal status of the three branches of government, the "enrolled bill" (the thing printed on fancy paper that actually went to the President for signature) is irrebuttable evidence that the law was properly passed. The courts cannot deal with inquiries into whether legislative process was followed; it's the legislature's job to decide what the right process is. They can't even look into whether the same text passed both houses -- as a matter of law, the enrolled bill is conclusive evidence that it did. Senate rules are enforceable in the Senate. But the Senate is the body in charge of enforcing them, not the courts.