My outdoor antique booth is completely exposed to sun / heat / wind / and more wind. So when I experimented with selling plants in vintage containers, I found out only the toughest survive. The toughest being... (drumroll)...succulents!
Succulents can take all the nature dishes out and still look fab.
Last year I sold several hundred dollars worth of succulents in old containers. They were the only plants that managed to survive last summer's furnace in the Midwest. These same little beauties survived last winter's brutal and prolonged low temps.
I have a pretty extensive succulent "nursery" but I am still looking for varieties that spread quickly and are easy to divide. Since there aren't many that flower (at least, not for very long) color and texture are also very important.
And of course, cheap is uber important. I try not to spend more than $1.00 for my vintage planter. Rusty - crusty planters look great in a grouping. I have my own compost pile, so I don't have to buy potting soil. I almost wipe out the whole succulent "nursery" by the end of June, but it is very inexpensive compared to buying plants as needed. I also maintain a big box of vintage planter accessories in case the whole thing needs a visual boost or there is a blank spot that needs filling.