Probably nothing. Transaction costs (including risk) swamp the value of a $1 online service. Among the risks is the low probability of a viable business of $1 transactions. Unsustainable business models make services unreliable in the long term.
To put it another way, you're competing with Dollar Tree's one dollar duct tape, tortillas, and spatulas.
To put it another way, you're competing with Dollar Tree's one dollar duct tape, tortillas, and spatulas.