Take new $100 bills. Wallet folds can cause the bill to be refused, however, no such problems on $20 bills.
Also note that money establishments or banks will not accept torn notes £ dollar or $ uk pounds and you're only allowed to take in a limited amount of cash in dollars etc. Check before you travel and don't try to be smart because as the laws state you can have everything taken from you if you do not declare what you have.
The rate is around 5 grievna to the doollar and the uk pound £ is 9.
Also the new £20 uk pound note in June 2007 was issued Keep in mind that until the government acknowledges the new notes, none can be exchanged.
But banks and cash points are easy to obtain money from your own country and are widely available. Some will only allow small amounts others will allow bigger ones. Pre paid visa cards are also good use as a safe guard back up.