Two questions decide this category, and only one of them is about packing.
Ask the courier first
Aerosols and anything flammable are restricted, and many services refuse them outright. Find out before you set a delivery price, because a refused parcel is a refund and a loss, and an underquoted one comes off your own balance. How delivery is charged.
Then assume heat
Creams, balms and anything wax-based soften, separate or melt in a parcel that sits in the sun. Say in the listing that a product is heat-sensitive, and tell the buyer in the parcel note to let it settle before opening. Packing beauty products.
The four options
Courier for most products, double-bagged against leaks. Your own delivery locally, which suits heat-sensitive items. Pickup for bulk and for anything restricted. Buyer arranges rarely.
When collection is the honest answer
For aerosols your courier will not take, for large bundles, and in the hottest months for anything that melts. Pickup terms are agreed before bidding with a collect-by window. How pickup works.
Combining wins
Products combine well by weight and badly by leak risk — each item in its own sealed bag, then a second bag around the lot, so one leak does not reach everything else. Combining is on by default and you set what each later win adds.
Questions people ask
Can I post nail polish or perfume?
Ask your courier. Many classify them as restricted.
Should I use ice packs?
Only with a service fast enough to make it meaningful.
Is cash on delivery available?
Only on Buy Now items where the store offers it, never on an auction win.