Here's my two cents. I don't know if you have shops down there that give you a guarantee buy-back amount if you trade in within a year or two, but it seemed to make sense for us. We have two little ones and they will both be out a lot this year (probably 30+ days if this year is anything like last). We went to a shop where we picked up used boots for both and used skis for one that: 1) were a lot nicer than the lease skis we looked at; and 2) cost only slightly more than leasing. BUT, we can sell them either to the same place (they told me they will definitely buy back both) either next year or the year after, or sell them on our own or through a consignment shop. So, at the end of the day, in the long term, we will end up ahead of the game. The used equipment we bought were items that were traded in as part of the buy back program.
We ended up not finding any used skis in my son's size, so we bought new, knowing that we can trade them in within the next two years for half of what we paid. It will be a never-ending revolving cycle, so we are ok with that. Assuming we trade them in for half off, then we will have spent about $20 more for new skis than we would have for used (if they had any we could have bought). But, my seven year old, who is as big a gear junkie as I am, will have new sticks for this year and he is beyond psyched.
Based on the amount we ski, and the numbers, it made sense for us to buy used/new under the circumstances. An old friend who coached for years warned me to be careful about buying at ski swaps, as sometimes the equipment may be so old that you can't find a guy to do any work on it. Definitely not a desirable outcome, and I don't trust myself to know what I'm getting at this point. Maybe at some point in the future, but not now. So, I played it safe and did it this way.
As a side note, my 7 year old watched, enthralled, as he got a good demo/lesson from the Swix wax guy at our local ski expo this week, so I see what lies ahead in my future!
Good luck and hope you find the right gear at the right price whatever you decide!