I would pay for real service - eg, if the dealer brought speaker to my home, set it up etc.
I would also pay "rent" if I needed to evaluate them at my home for an unusually long time.
If he loaned them to me for a few days and I had to carry and set them up myself, then I wouldn't pay anything except perhaps leave a deposit if requested.
I would not pay for in-store demos. Showing something you are trying to sell is part of retail. The customer may not buy or buy elsewhere - all retailers take that chance and those who can't should not be in retail.
I would also pay "rent" if I needed to evaluate them at my home for an unusually long time.
If he loaned them to me for a few days and I had to carry and set them up myself, then I wouldn't pay anything except perhaps leave a deposit if requested.
I would not pay for in-store demos. Showing something you are trying to sell is part of retail. The customer may not buy or buy elsewhere - all retailers take that chance and those who can't should not be in retail.