Dispatched to investigate the findings of two other companies. Client stated that the system had frozen up before. Another company that has been maintaining the property found a leak in the evaporator coil. It was replaced today and I documented the data plate for the evaporator coil. The other contractor told the client that the compressor was defective and was unable to pump properly. I found out that this was not the truth, but it just needed more refrigerant. The client was trying to get in contact with the company that changed out the coil to tell them that my findings were that they needed to return to top off the system. After 15 minutes of waiting, client stated that he would like me to top it off, I told him that it would need at least 3 pounds of R 410 A @ $230.00 a lb. 4#