He and his wife Liz Maihock Beloff moved to Los Angeles where they become regulars at the monthly Rose Bowl Flea Market.

Beloff expanded into DVDs as well, quitting his job at Billboard, he and his wife created Flea Market Music, Inc.

The rise in popularity of the ukulele, and the company's sales, have continued to grow with over 600,000 Jumpin' Jim's books in print.

[9] The concerto was played by Beloff and the Choate Rosemary Hall Orchestra in Germany and Austria in June, 2016.

[10] Finding the availability of good ukuleles to be rather limited, Beloff was interested in developing an inexpensive, quality instrument.

[6][8] Located in Sheffield, Massachusetts, they use American made parts and materials to produce their instruments using environmentally responsible methods.

In 1995, Beloff produced the first annual UKEtopia concert at McCabe's Guitar Shop in Santa Monica, California.

[13] The 10th UKEtopia included two song sets from "Mr. Ukulele," Dan "Soybean" Sawyer, Fred Sokolow and "King Kukulele," and was summarized by Tom Teicholz in The Jewish Journal of Greater Los Angeles.