An AC doesn’t “loose” refrigerant. You should never need to recharge your air conditioner with more Freon — unless there’s a leak. One of the biggest headaches people have with air conditioners is the system losing refrigerant though a small leak in the system. Larger leaks are typically easier to find in a air conditioning system because the will leave evidence such as a oil stain, a visual hole or crack in a coil, and in some cases when trying to add refrigerant you may even here the hissing sound of the freon escaping.
We know replacing the whole unit because of a refrigerant leak seems extreme. However, if you AC unit is older than 9 or 10 years old, you may waste money with fixing a leak + recharge when the old unit may go bad sooner than later. Coast2Coast AC will be up front and explain the best course of action.