remember when you were a beginner and didn't have a clue what board you should ride?
I feel like everyone has or remembers that first used POS board they bought and thought it was amazing (even though you couldn't ride the thing). Year or so later you look at it saying "What was I thinking"
Rode hand-me-downs until I was in high school so had a pretty good idea what would work for me by the time I actually purchased a board. Do agree with a few others on here; if you're asking the question here, it's bothering you enough to just be honest. If they like the board they are gonna buy it regardless.
I never really bothered with it. I bought two or three boards when I was a beginner that didn't work for me and I just sold them to other people (and got my money back). I don't think it's wrong to sell someone a board that may not work for them, just don't sell it to them for more money than they can turn around and get for it if it doesn't work out for them.