Can I leave all chametz in one or more kitchen cabinets, close it with a label “chametz” and sell all this chametz to the goy?
It will be physically present in my possession, but it will not be mine. Or I have to remove all chametz totally out of my home?
Can I do the same with non-kosher for Pesach keilim? Just to leave them in their place in kitchen cabinets, seal it with a label “chametz”, and not to open during Pesach?
It is certainly permitted to leave non-kosher for Pesach utensils in one’s possession over Pesach, and there is no need to seal off these cabinets.
For chametz products, many sell more chametz products to a non-Jew, and seal off the food in a labeled cabinet. However, some prefer to avoid relying on the sale for proper leavened foods, and are careful to clear out all chametz before Pesach.
For expensive items, such as whiskeys and so on, you can certainly act leniently, and as noted many do so. For cheap items, it is perhaps advisable to throw them out, though it is permitted to rely on the sale.