Don't know anything about the particular equipment line you mention; an alternative would be end of season sales at Tractor Supply or similar. The $80 S&H you mention would go a long way toward a 50-gal (or size you desire) 3-point hitch mount cluster-head spray rig complete with PTO roller pump. You could add options like fold-up spray arms or different pump or tank.
Unless a golf course is being sprayed I predict most operators will find a cluster-head much easier to use and suffer fewer maintenance issues than a boom configuration will. First time the boom snags 'anything' (fence, brush, pond dam, hummock, stump) it will be learning experience. And it will snag something. Wind will be the only consideration in using a cluster head---will need a light-to-zero wind speed compared to boom.
Consult your state university extension office for how to calibrate and use the sprayer. Investigate admixtures and adjuncts to enhance the process. Please don't start spraying without an understanding of the system: gives a bad name to all agriculture if your drift takes out roses (gardens, ornamentals) a half-mile away. Believe me, it can.
Please post back your continuing experiences so we may all learn.
