To avoid the need to empty you inventory because of lack of space, keep on crafting and selling items all the time. Visitors will always pay more for Crafted Items as well!

If your inventory gets full, you might get stuck as you progress through the quests, so you have to be careful to manage it properly by crafting and selling items.

Try to always be crafting as many items as you can at the same time!

To achieve this, make sure to have multiple of the same suppliers in your park and to upgrade them as well!