R-22 in the bulk bottles used by contractors runs about $30-40/lb range in most areas, so marked-up cost typically runs about $40-100/lb, though some are taking advantage of the phase-out of of R-22 to jack prices up. However, at that price there would be a service/ labor charge attached - commonly in the $100-250 range to do the addition of gas and adjusting the gas amount to obtain the desired operating pressures (which if done by a reputable contractor means an operating test to make sure the operating pressures are correct, though some slipshod contractors will just guess what the static pressure should be to give approximately the right operating pressures, a practice which can result in a good 10-20% reduction in operating efficiency in some cases.
Other contractors roll their labor cost into the gas cost and just charge a flat rate per pound for the gas, which includes the gas and labor - so more commonly in the $100-150 range, though $200 does sound pretty high to me.
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