I can't imagine my parents paying 2 months up front. I had a hard time getting 2 weeks as a deposit.
I do 2 weeks(non refundable) up front to reserve the spot, and that is applied towards the last month of care(assuming adequate withdrawal notice is given.) I removed a trial period from my contract, as I found some people were using it as temporary care until they got into a centre, and then not wanting to pay, or wanting a refund. I increased my notice of withdrawal to one month for parents, and I found no one tried to run away on last payments. I take 6 months of postdated cheques at a time so I'm not hunting for payments(and payment is either due all on the 1st, or divided between the 1st and 15th) If they give inadequate withdrawal notice, then the last 2 weeks are forfeited to compensate me for lost wages.