We just purchased an AT&T calling card at Walmart. Before I bought it, I called AT&T to actually see what all of the charges would be and any hidden charges. So many hotels charge to use their room phones. We are going to use the card at a pay phone. The only charge for the card is 9 minutes everytime you use it at a pay phone. Which is cheaper than 75cents every time you use the hotel room phone. This charge is for any pay phone.
Ex: If I use the pay phone 5 times, which is the amount of times I plan to call home, it will deduct 45 minutes from the card. I bought the 120 minute card for $10.00. This will give me 75 minutes to talk, which is more than plenty. You can also check the amount of minutes used on the card.
There is a card for $5.00 for 60 minutes. Plus they sell some with more minutes. We are going over Mother's Day, so I thought I better have plenty minutes.
Sure we could take our cell phone, or use other options but we found this to be the cheapest. I have heard horror stories of some getting the hotel phone bill and well you know! Scream!This is what we have always done on each of our trips.
Hope this helps!