Due to a strict and clearly communicated system, I am rarely messed around. Sometimes you just can’t avoid the odd let down, which Matthew refers to as “bad debt” which you just write off and move on as you can’t exactly go to court for the sake of £30.
My system is: Upon booking a first lesson, I inform the student straight away that the first lesson is cash in hand and that 48 hours’ notice is required for cancellations. I also inform them that upfront monthly payments are required after their initial lesson if they’re happy to continue.
For first lessons though, there’s literally nothing you can do except trust them. I haven’t had a problem too often though, but if you need to cover yourself for those first lesson no-shows, I have a teacher that takes upfront paypal payment online even for first lessons, which also includes a £10 deposit.