Expensive Telephone Bills

My hubby is often making phone call to his customer at home now. I should be very happy with his business growing fast and good. However, our home telephone fees have become very expensive now. Because he call to oversea quite often too! I do not think is a good idea to continuous using normal phone line to call oversea, this really cost too much for us. So, I was thinking that should we install the VOIP Small Business phone systems at home? I heard that using VOIP to make oversea calls will save a lot, and the quality of voice is very nice too. I will recommend this to hubby and get it install if he have no rejection.