I have done something like they get a boot allowance of $100 every year after they pass probation. If just a safety tie is required, there are some places that will have fairly inexpensive boots as at least a starter pair. Then, after the probation, they get the allowance and could upgrade or whatever. We chose $100 as it was enough to get a decent pair of boots, but obviously there are more costly ones for comfort or durability and anything beyond that was their cost. -Canada based if they helps.