This is more or less yearly routine maintenance. If your unit works fine from year to year, then there is no need to hire a company to come do this for you anyway. It will end up costing you more. Every time they hook their gauge set up, they let out some refrigerant, so when they are checking the system, it will be "low" because they just let it out. So you get charged for the missing refrigerant they let out.
If its working fine, there is never a need to have a gauge set hooked up to your line set in other words when your "having it inspected".
This is just a simple wash out for summer time anyone can do.
Same goes for your furnace in your home before winter. But you use brushes and a shop vac. to clean it out.
~F~
