I always include this measurement when I sell one, I just figured it was common sense.

I'm more interested in the layout on a used ball than the span. If the bowler uses finger grips then it's easy enough to just do a pitch plug on the fingers and then a full plug on the thumb and keep the same basic layout. If I have to completely plug (and move) both fingers and thumb then it's a much bigger deal. 

I agree with Charlest and gizmo i can throw my brothers equipment but his finger pitch's are way different than mine so after about half a game my hand and is killing me so I can get the gist of how a ball is going to roll for me but can't throw his stuff for a prolonged amount of time.

I would like to add a point if only for future reference.

For many newer bowlers, I will recommend buying a used ball to start.  This way the bowler isn't investing too much in the event they don't pursue the sport any further.  Many times I find out they buy a ball that to them feels like it fits, yet in the truest sense doesn't.  This can cause physical problems as we all know.  But to them, they don't know any better.

But much like buying a set of golf clubs off the rack, buying a used bowling ball most likely won't be the right fit for the new owner.  Yes span is an important part of the fitting process, but as charlest has stated, pitch is just as important.  Combine with this the actual drill pattern and the next thing you know, you have a ball that makes your hand hurt and doesn't react as you would like.

If you buy a used ball, go the extra step to have the ball drilled for YOU.  You wouldn't buy a new ball with someone else's drilling specs, so why buy a used ball that way.  You will score better with a properly fitted and drilled ball just as you would in golf with a properly fitted set of clubs/shafts.

I usually inquire about the span and pitches when buying a used ball. One seller on here, who I have multiple purchase from, has the exact span and pitches I use.  Always check his for sale posts.

TT

You can't be messing around with just the span. I agree with everyone in the thread. A 4 inch span with 1/2 forward in the thumb is totally going to be different than the same thing with 1/2 reverse in the thumb. Pitches matter even more than span, IMO. Cav, do yourself a solid and always get your stuff fully plugged and redrilled, unless the existing holes are EXACTLY the same pitches.

Used balls need to have the span adjusted proper and the pitch adjusted in the fingers and thumb properly.   I've always sold used balls fully plugged but recently people have complained about that and want balls not plugged and ready to drill.

The majority of people these days just leave whatever the finger pitches are and just re-do the thumb thus they don't like fully plugged used balls.  This is a mistake in my opinion.