I would suggest that you look into mini-split heat pumps. Much higher efficiency and likely quieter. Merv 16 filtration while an excellent filter has a whole lot of pressure drop across the filter. You may need a much higher horsepower fan to deliver the air across that filter. I am not saying it cannot be done. I do not know Unico's specs on the AH, but would suggest you ask how a mere 11 or 12 might impact the size of the fan.

Thanks Jackfre for the valuable suggestion. We might consider to downgrade the merv 16 to merv10~11. However, we still aren't sure about the quote, and hesitate to make any decision. Any idea about the quote?

Waiting for two other quotes now.

Thanks alot.