“Bare Cast Iron: Anything from Smithey.”
Just buy one. Make it special. You've got a few ways to go here: Enameled Cast Iron: -Le Crueset or Staub dutch oven Bare Cast Iron: -Anything from Smithey Stainless Steel: -Get something unique that most people won't already have, like a Rondeau or Saucier, from Made In, All Clad, Hestan, or Heritage Steel.
“Smithey Deep Farmhouse Skillet (carbon steel).”
Some are a little spendy, but my set is: Smithey Deep Farmhouse Skillet (carbon steel) made in Stainless Clad Saucier 5 qt De buyer mineral B Pro 8 inch carbon steel fry pan Vintage Wagner 10 in griddle skillet (eBay for cheap) Staub 5 qt Dutch oven (really wish this were a 7 quart) I don’t really have the need for anything else (except that 7 qt Dutch oven…) and I do a ton of cooking. These are all BIFL in my opinion. I feel the best bang for my buck was the de buyer pan (and if properly seasoned an absolute dream to cook with). I used to try green pan and nonstick, and even being super careful, they’d barely last a year. Have had all these pans over a year ago and they still look brand new. I like *love love* them. ***edit to say my sauce pans and stock pot is old nonstick that I plan on replacing with made in stainless steel as my budget permits. These aren’t chipping and are over 10 years old now. My best advice is just to acquire these as budget allows. It took me awhile to acquire the ones I have now. But the quality and BIFLness is worth the wait and effort. Also, many antique stores have so many amazing old cast irons that are pretty cheap and a good place to start.