coin collecting can be fun, but dont expect money in it....
the biggest reason is there is never jumps in prices of coins, so the long term return is nothing, buy a coin for $10 and in 10 years it will probably be woth $10-11 dollars.
selling your collection is another problem. dealers that sell coins 99% of the time only buy wholesale, then turn around and sell retail. so you wont get full value from them for your coins.
it has to be one of eht oddest / non-money making collections out there LOL.