The cost of a virtual number depends on the country, type of number, city, or operator;
When you buy a number, you pay for connection (one-time fee) and subscription (you can choose 1, 3, 6, or 12 months subscription);
Cost of incoming calls and SMS forwarding depends on the type of forwarding and destination;
The cost of outgoing calls and SMS depends on the destination to which you are calling or sending SMS;
You can check the cost of numbers and rates for calls or SMS in the section "Pricing".