Sure, as long as you ask the question before you bid and win one of my auctions I’m always prepared to do a layby deal.
The way it works is you have to do a Buy Now if it is an option or win the auction with the highest bid. Once the auction closes you will receive an email with the payment details. You’ll need to make your first payment within 3 days and complete all other payments within 40 days so that feedback can still be listed.
Also my Layby deals are no different to other successful auctions, once you win the auction you are committed to completing it.