Try now. pay later. This is chiefly a UK idiom used to describe business agreements between friends wherein the purchaser pays for the product upon receipt of a future transaction.
In order for this arrangement to work for both parties, the seller is best insured by
- having a substantial discount on the cost of their purchase from their supplier ;
- having a sufficiently desirable product ;
- a shortage of time available &
- great trust in their "friend" whom they are selling to.
There is, of course, the potential for either party to get screwed over—either by being unable to receive money for product already "sold" or by being unable to procure in the future.
The expression stuck in my mind as "on the tick" but it seems that the article "the" is more commonly omitted.
User dpatrickb of the Urban Dictionary defines the term thusly: Literally 'on the clock.' Used in regards to something with a strict
time limit, especially drug deals in which you get the product for free
and pay once dealt. The emphasis here is on the waiting aspect (from the seller's perspective) of being on tick.
Equally valid is the entomological sense of the word tick, as the arrangement may, over time, literally suck the life out of an otherwise invigorating experience.
This practice is also sometimes used in other parts of the black market, such as amateur porn or bookkeeping.
Additionally, the expression may originate in the sense that the vendor keeps a list of who owes what, and "ticks" them off the list on payment as NaughtyJim of UD notes.
Hardly a practice suitable for legitamate businesses, given the poor track record of human nature, but— hey, any way to turn a quid, right right?