Once they've done a month I start sending them on courses.
Small stuff like first aid, chipper etc I just write off.
Climbing, saws etc it's written into their contract and MORE importantly, I ask them before sending the bespoke training agreement for that course - if they're happy with said agreement.
Agreement is that they pay it back if they leave within 24 months (I also add wages lost for the say 6 days they are off, to make the value larger).
I then write into the agreement that the balance reduces by 1/24th for every month worked. Plus a few other conditions such as if you're fired and so on.
The main reason to do this isn't whether it's enforceable or not, but most employees genuinely think they are tied in for 2 years when realistically they could easily pay it and leave.
I will say all of my guys are here by choice I know I'm coming off as a tosser here.
You absolutely can write into the contract and training agreement (which they must agree to) that any deductions can be removed from their final salary payment. I have had this confirmed and documents checked over by our HR consultant. Is it worth the battle? No, the last climber that left had £400 balance left. He swapped it for the 3 days holiday in owed him and called it quits.
He comes back and subs to this day (is a barber 5 days a week lol)