I can borrow anything because of long-standing relationships. But, if I were a dealer I would not let anyone borrow gear for an audition. These days, people audition stuff with no intention of buying--they try dealer gear and then go looking for better deals on the internet (used, grey market, whatever). I know a dealer who lent two amps to a person and later found out that two other several other dealers did the same; the "customer" held an audio shootout with his friends just for fun and then returned the gear.
Dealers basically lend their floor models out, which means they are out of a demonstration piece until it is returned. They cannot lend out something "new" out of the box because it is then no longer "new." One has to wonder about those on-line dealers that offer a limited trial period; do they sell a returned piece as new? Would you like to buy a new speaker that may have been shipped around to various other people and having undergone such additional handling, potential abuse from someone cranking the volume way up, etc.?
If you are a customer that is fair to the dealer, dealers will do quite a bit to accommodate your plans. I once asked a local dealer about the high end linestage models of two brands he carried. He had neither models in his shop. But, he was willing to buy both models as demonstration models (the lowest price from a distributor) if I promised to buy one of them (handshake deal). He got in the Levinson No. 32 linestage first, I tried it at home, liked it, and bought it without requiring him to bring in the VTL model I was also interested in. Another local dealer built a pair of customer speakers, each is more than 4.5 feet wide, almost 9 feet tall and about 4 feet deep. It took a rental of a mini tractor to make the deliver/install at the customer's house. The customer's wife hated it and the dealer took the speakers back. I don't know what the financial arrangement was for the return, but, can you imagine how hard it is to find a space for two such giant speakers and how hard it must be to find a new buyer? Such service still exists, but it only exists if there are both good dealers and customers and not where both parties are trying to get the drop on the other.