A lot of the time purchases of one product encourage purchases of another. A freebie or a loan of a particular product automatically creates a demand for something else. Customers sometimes require a nudge to buy from you rather than a competitor.
An upmarket supermarket chain were well aware that people like to throw an occasional party. Their products were no different to any other supermarket’s though. Therefore to entice customers to shop with them rather then their competitors was to offer a free glass hire service. The supermarket would lend you glasses for your party for free, on the understanding when they were brought back they were clean. If any breakages occurred they were charged £1 per glass.
Make sure there are no hidden strings. If there are the element of trust is lost and will backfire.
Fully accept that some people will abuse your trust, but the majority won’t. Do not get too hung up about the people who do.
It is important that the freebie or loan does nudge the customer into buying something profitable.
Have means to recover any loaned goods, and just in case, make sure you can afford to lose them too.