Below is a link to a PDF with explanations and recommendations on how to fill out the Licensing Agreement they will be sending if they choose your images for exhibit or reproduction.
Check it out. Hopefully it will help you move forward with this opportunity.
The choice of “exclusive” or “non-exclusive” may need more explanation, so here it is…
“The “exclusive” means for a certain type of merchandise product that we agree with each other, the artists should avoid giving rights to another company or firm by using that painting to create that type of product and sell in the market for profit. The reason here is to prevent copycats and unfair competition.
For example, if we sign exclusive license with an artist for a specific image on a specific type of merchandise product, say iPhone case, they shouldn’t agree to produce iPhone case with another company and sell it on market. But they are totally fine to ask other companies to produce greeting card, postcard, pen, magnets etc. that are not specified in the agreement. Also she can produce the iPhone case for herself, friends or family use.”