Yes they do. Especially if in a prime focal area.
Yes, in general Mint State coins do have higher values.
This is only the case for some 1950 British coins. Proof coins should be worth more simply due to the amount of work required to produce them. Proof coins are produced in a finite quantities for a given denomination and year. An "Uncirculated" coin is one that goes through the usual minting process, but is removed before it starts banging and scraping against other coins and developing the marks and scratches associated with circulated coins. Uncirculated coins are an unknown quantity after they leave the Mint since they can be so easily circulated and subsequently lose the grading of "Uncirculated". It is a matter of "supply and demand". Less "Uncirculated" coins for a given denomination (or year) are known to exist than Proof coins of the same denomination (or year), therefore the collector value of the "Uncirculated" coins is greater. The same apparent disparity of value occurs for many coins and years.
These coins are still in circulation and are worth 1 cents unless they are uncirculated.
Brilliant uncirculated coins sell for 50 cents or more, depending on the grade of the coins. Brown coins are 10 to 25 cents.
There is no such thing as a Presidential quarter. These are dollar coins. They are not gold. They are brass. They are worth around $2.00 in uncirculated condition. These coins are very common.
In circulated condition, face value only. If they're uncirculated or proof, you'll need to be more specific as there are 3 mint marks and 6 denominations to choose from.
There's nothing stopping you from spending uncirculated coins, but they are typically worth more than their face value. That is, your uncirculated nickel may be worth 10 cents. And as soon as you spend them as regular change the coin loses its uncirculated status. You'd be better off selling uncirculated coins to a collector or a dealer. Most will be happy to buy your uncirculated coins for more money than you would get by spending them as change.
How much is a 1960 Hong Kong Modern Uncirculated Type Set worth
As of 11/2008 a set of uncirculated 1971 U.S. coins retails for about $9.
The 1977 US Mint Set (12 coins) has a retail value of $10.00
Do you mean as collectibles or for their exchange rate? If you have that many coins you'd need to know their dates and mint marks. In general, 1-pf coins dated 1969 and later are worth more than face value only if they're uncirculated, and coins from 1948 to 1968 are worth more only if they're either uncirculated or nearly so. As for the exchange rate, at the time these coins were discontinued in 2002, they were worth about 1/2 of a U.S. cent. However, it would be very difficult to exchange them now unless you were at a major bank in Germany.
If your 1971 coin is a uncirculated example it may be worth about $5.00 because the 1971 & 1972 issue coins were not included in the Uncirculated Mint sets sold from the Mint in those years. In general none of the coins made for circulation have any silver and are not worth more than face value. Only proof and uncirculated collectors coins sold from the Mint have premiums. The Mint did offer Proof and Uncirculated coins in 1971-1976 that were struck in 40% silver.