19 gpm at at least 3000 psi will do fine. Lighter the better. I like the bobcat brushcats but they are heavy. I like the roller wheel and the float linkage but it's not 100% necessary and adds significantly to the weight. My davco never had that stuff and worked fine and was a lot lighter but it was high flow. Look for a used ammbusher. There were a lot of those made a few years back.
"Life is tough, but it's tougher if you're stupid."