I personally try to take and move on within a fortnight , how far often depends on either 1: Work Commitments , regular trips to Brum and Suffolk , or 2 take them to my TB hotel on Anglesey which receives a good number of visits March - October.
I normally try to swap like for like but tend to place a coin without taking anything if i think ive had one for too long.......
However not long after i started i got an email from a grumpy TB owner complaining because i had had his TB for 2 days...... Won't post my reply on here