When you are fully satisfied with all the arrangements agreed with your partners, you may wish to write a short exchange agreement stating the dates of the exchange and listing all decisions taken. Sign it and send two copies to your exchange partner. Ask him to return a signed copy if he is happy with the agreement.
At this stage you have made a binding agreement to go ahead with the exchange. Withdrawal would cause great inconvenience and expense to your partners. Any members known to have broken a firm agreement will be excluded from any future listings.
If you should get an attractive exchange offer after already agreeing to an exchange, why not suggest an exchange at a later date? Just breaking an exchange agreement because a better offer comes along is taboo among home exchangers.
In the case of unavoidable cancellation (death, illness, redundancy in the family), telephone your exchange partner immediately. If at all possible arrange an exchange at another time, or failing that arrange for a friend or neighbor to take your place.