To help you in your exchanges in case it is not possible to do it reciprocal, we created the JollyKeys system. You will be able to stay at another member's home without them staying at yours. You will transfer as many JollyKeys as nights you stay at their home. Your host can use them to travel to other destination of their choice.
For full details on how to use the JollyKeys and how to get them, see this file.