etching: could it be valuable?

[sumik]

Any antique appraisers out there? Customer brought in an etching by Ernest C. Rost, copyright 1890 Fishel Adler Schwartz, New York. Has a boat on the Lower left corner. There are plate ridges, but it appears to be a paper mounted on top of another. Size is 10x20. I am no expert, but am thinking this could be quite valuable. What do you all think? (Had one once, smaller than this one in worse condition insured by customer for $12,000.)