There's a neat website, I think it is
www.minimus.com, that have small sizes of all kinds of things you can order, great to put in your suitcase so don't have to buy large quantities when staying in short-term rentals. When we were recently in Hawaii, we had a couple of condos, and we bought smallest sizes we could find, used what we needed, threw the rest out. We also for instance both like mustard on sandwiches, so we just bought mustard instead of several choices, since we were only in each condo several days.
You will find with most short-term rental properties you will have salt, pepper, spices people leave, somewhat of a collection. The small packages of condiments is a good idea, as better than leaving guests open bottles of ketchup, mustard etc. It freaks me out when I see these in a rental property, especially if they look decades old, lol, with crusty ketchup and mustard around the cap, gross. Some issues of hygiene here!
Walgreens, I think, may sell smaller sizes of things and
Walmart has a section of travel items, but I think Health and Beauty supplies.
It is also a good idea to put some storage bags in your suitcase, without the cardboard cover, always useful for foods, etc., left overs. I also throw in some trash bags, although some owners will leave lots, others few...no consistency. So I pack them just in case I need them. They're always useful for dirty laundry, too. Dishwasher tabs is another easy thing to pack so you don't have to buy a whole lot of them. These are just some of the things I always throw in my suitcase when I'm renting a condo. Sometimes they are already there and I don't need them, but saves us from buying them there if we do.
Sandy