The Spanish giants are reported to have agreed a £105m fee with Spurs for the Wales international.
"Is he worth £100m? Who can tell? Who can tell what something is worth? Everything is worth what one club, one person, one company, is willing to pay," The Herald quotes Laudrup as saying. "It's like buying a house.
"We talk about it like merchandise and I don't like it, but it's fact that if one person is willing to pay so much for one player, then he is worth it."
Arsenal manager Arsene Wenger has labelled the world record fee as a "joke".