What a one-off print actually costs
Why a 20 mm part is not a two-dollar part, and how material, machine time, and a minimum order show up in the price.
A spool of PLA is cheap. The minute it takes to start a job is not.
The P2S still has to heat, the file still has to be checked, and a failed print still uses filament. On a tiny part the plastic might be a few cents. The handling, the bag, the label, and the card fee are dollars. That is why keychain tags and fidgets are sold as sets. A single tag cannot carry an $8 floor and a 60% contribution margin without looking absurd next to a bin of mass-produced tags.
Larger parts flip the other way. A desk tray or a headphone stand uses enough machine time that the material and the depreciation show up beside the labor. The public price is the full cost divided so the shop keeps the target margin after Stripe and a small remake reserve. Sales tax is added at checkout and is not part of that margin.
If you already have a closed STL or 3MF, the quote tool measures the volume and the box. Anything over 256 mm on an axis stops there. The printer cannot grow.