Cost to repair a heat pump in a condo unit

So the heat pump in my condo unit (GTA and ~2 years old building) stops working recently and a technician came into the unit, did some initial testing, and determined that he had to take the unit out to do further testing. A day later, the technician calls back saying there is a leak and the cost is going to be $780 + tax bill (which later reduced to $740 + tax after some negotiations)

I don't have much experience with HVAC repair costs and wondering if someone in the forum can comment on if the repair steps and charge make sense?

Reply from the HVAC company ($90 per hr. and $100 for recharge the refrigerant)

"As you requested, here is the breakdown of the work we did on the heat pump unit.

It took about 1 hour for technician to assess the heat pump unit in the suite. It was concluded that unit was out of gas, and since it is illegal to put on gas in heat pumps when they are in condos' suites, we needed to take the unit out and bring it to the shop to test where the leak is coming from in order to be able to put on gas.

Technician took one hour to refill the heat pump unit. And once, it was full, our technician started to do a pressure test on it for two hours to find out where the leak is. After finding the leak, we had to do another test called negative test which takes about 30 minutes. In addition to that, it took another 1 hour to recharge the heat pump unit with R410 refrigerant gas - 21 ounces in total.

And, it will take about 1 hour to reinstall the unit again in your suite.

Repairing heat pumps involves a lot of labor and in your case, it took our technician more than 6.5 hours to diagnose and repair the unit. In order to find out why unit was failing we needed to bring the unit to the shop for testing."

Any feedback is appreciated.