You are right, it is impossible to afford mobile or landline for international calls. Calling cards are best to make international calls. Their importance become much more especailly when you are making calls on regular intervals. You can surf the internet and compare different companies calling cards to find the best one to call Moldova on basis of cost and time.
Moldova is relatively expensive for calling.
Many long distance and calling card providers offer cheap rates, but quality of call is terrible or at least difficult to speak.
I found a site which allow to see and compare rates and calling cards from many telecom providers.
I use Lyca Calling card. Not perfect, but really good for money. You may see the list of all calling cards for Moldova at http://www.ontariophonecards.ca/moldova.calling-cards
I used to make international calls with Pennytalk, and it was very reliable. The only downside was (at least at the time) a "per call" connection fee of something like 59c, so you really had to talk for 20-60 minutes on a single call before it was a lot cheaper than other cards.
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