"Circle of Master of the Prodigal Son" is copy after Adriaan de Weerdt.

Ader, from France, sells on 4 May 2018 a "Dutch School, ca. 1600, circle of the Master of the Prodigal Son" Ruth and Boaz, estimated at 800 to 1,200 Euro.

The style reminds me more of Frans Floris than of the Master of the Prodigal on, but in the end this is just a decent copy after an engraving by Philips Galle after a design by Adriaan de Weerdt, which is kept in the Albertina in Vienna.

The painting has changed the backgorund though, making it a bit more lively and Flemish (Breugelian) in style. A nice enough painting, and worth the estimate, but nothing more.

"Dutch School" is copy after English engraving

Doyle, from New York, sells on 24 May 2017 a "Dutch School, 17th century" Orpheus and the animals, estimated at $4,000 to $6,000.

While the topic has been treated multiple times by Dutch and Flemish artists, this version is probably British, as it is based on an English engraving from ca. 1650-1670, as can be seen at the British Museum website. The engraving is more detailed and richer than the painting, which lacks some elements (changed to the little stream left of Orpheus). As the painting is worse than the engraving, it is obvious that it is based on the engraving. It may well be early 18th century. The estimate is too high for this copy.

UPDATE: sold for $3,437, still seems like plenty for a good copy after an engraving.

UPDATE 2: For sale at Hargesheimer on 17 March 2018, with the description "DUTCH/FLEMISH SCHOOL Master, active in the second half of the 17th c" and estimated at 2,800€, which is still too much and which would mean a loss for the previous buyer anyway.

"15th century Old Master" engraving is a 1518 Lucas Van Leyden work

Arthaz, a New York auction house, sells on 16 June 2015 a "15th Century Old Master" engraving of a "Royal Ceremony", estimated quite widely at $500 to $2,000.

It is a well-known 1518 (so not 15th century) engraving by Lucas Van Leyden, showing Esther before Ahasverus. It is known in three states, no idea which state this is but the engraving looks crisp and detailed (the paper has some damage and issues though). You could have bought a somewhat damaged copy at Christie's in 2009 for £1,000, although another very fine copy (pictured) fetched nearly $9,000 at Gallerie Bassenge in Berlin the same year. I guess this one will not exceed the $1,000.