David Zimmerman moved to Purcell, Oklahoma to work for Doug Milholland in 1999. After 6 years of working as an assistant for Doug he moved to Scottsdale, Arizona to continue learning as an assistant trainer for Troy Heikes. In the fall of 2006 he returned to Purcell to begin a training business with his girlfriend, Sue Waskowiak.

In 2002 Sue moved from Westboro, Wisconsin to Purcell to take a job with Doug Milholland. In 2005, after 3 years of training and showing for Doug and his clients Sue took a job managing and training for Jerry and STV Dalpias at the Painted Moose Ranch.

Today Dave and Sue both work at the Painted Moose Ranch where they train outside horses in addition to the ranch owned horses. Their goal is to breed, raise, train and sell top quality reining horses for reasonable prices.