These are my thoughts about optimizing the use of instant film formats so as not to go bankrupt with your new addiction.
I currently use four formats. For my Polaroid SX70 Alpha SE, I use Impossible Project SX70 film–it provides vintage Polaroid color, size and feel but is expensive. With my Polaroid Land Camera 250 and NPC 195, I use Fuji FP100C and FP3000B–both are great to use but increasingly in short supply (3000B) and notoriously bad in low light (100C). With my Instax SP-1 printer and Fuji Instax Mini Neo Classic, I use Fuji Instax Mini film–it’s fast, colorful, and retro but provides smallish prints and is moderately expensive depending on who you buy from. My Polaroid Zip printer uses Polaroid Pogo and Zink photo paper–this paper contains the ink required for development and is relatively cheap but grainy and and a bit dark.
So what to do?
Use Pogo/Zink casual street shooting where you don’t mind giving away shots in exchange for cooperation or to break the ice with your subject and/or provide a keepsake. Each print costs around 50 cents.
Use Instax prints for more nostalgic, special, giveaway moments. You’ll spend about 80 cents per print.
Use Fuji FP100C and FP3000B (even less as it’s discontinued) when you want to capture classic moments that allow for slow, methodical shooting. The 100C film is the color version and requires a lot of light and the 3000B version is black and white and performs wonderfully in most environments. Cost varies but prints will cost you $1.10 on average for the color film and $2.20 per print for black and white.
Use Polaroid SX70 film for fun and to capture fond memories with a camera that is a nostalgic conversation starter but make sure you have lots of light, patience and money as it’s the most expensive of all at $3 per print.
The only other consideration is whether you’re concerned about having digital versions of your photos in addition to the film prints. Using either Pogo/Zink or Instax means you have a digital version of the picture (assuming you used a digital camera and transferred the photo to a Polaroid or Instax printer) and don’t need to worry about single shots that aren’t preserved beyond the print. The other Fuji film (100 and 3000) and Impossible Project film require you to scan the emulsion or the prints before you discard the negative or give the print away, otherwise what you shoot is preserved solely in the tangible print and there is no digital record for further processing or printing.
My only other advice is to shop around for the best film value by buying from reputable sellers in bulk when you can if the bulk prices are less than the cost per individual unit. Bulk purchases aren’t always cheaper but you might save more money on shipping when you buy in bulk. If you have a lot of expired film, get a small refrigerator and keep your film cool to maintain it for a longer period. Instant photography will hone your skills as every shot costs money and you’ll want to minimize mistakes to maximize keepers. There’s also creative value and surprise in the nuances of the instant media and sometimes the shot you get may not be the one you intended but it’s a better shot creatively. Take your time and enjoy the art that is instant photography.