To be honest, I doubt Barcelona still has a lot of money right now. They also will experience a problem with players' salaries if they are trying to force signing more top players. They may sign Marcos Alonso for free, but they must pay his salary, right? While Sergio Reguilon, still has a contract with Tottenham until Jun 30, 2025. Tottenham won't let him go and must set an expensive price if the player really wants to leave.
I really don't know how much money they have left now. After spending that much money it really makes me feel like they still have some money left. Because they have completed two transfers for a big amount of money like these were not a big deal at all. You are right about the salary topic too. They must think of their expenses for salaries and bonuses in the future too and act according to that. When it comes to Tottenham's decision I also think that they wouldn't sell him while they are in need of him.