I plan to buy a new laptop to replace my 10 year old one. Can you transfer what is on my old one onto my new one at the time that I buy the new one. If so, how long will it take and is there a charge?

Yes they will walk you through it or can do it for you. No charge for the walk through (migration s/w)

Just tell the guy you won't buy it, unless they transfer the stuff over for you. But be sure to check their work. Tell them you want to see it on the new laptop, before they delete the old one. Any sales person with any gumption is going to take care of it for you. And I would go to other stores, if the sales person wouldn't do it for me, until I found one who would. Price should be the same, or most places will price match. So that shouldn't matter. Good luck. Hope you enjoy the new computer. Oh, and make sure it has at least an SSD hard disk, or much more preferred. An NVME drive. This will make it really snappy, like a really good phone is. My HP Envy 13 has an NVME, and I'll never buy a computer without one after owning it. It's so quick! And make sure you get something with good battery life/extended battery. Mine lasts well over 10 hours, and again. I could never go back to a regular battery after owning this one.