Air Conditioning - replacing heatpump

hello i'm remodeling my basement and have an old heatpump used for my central air. i'm thinking of having this replaced with a new central air unit. i'm not too sure that this cold weather is the time to have the air conditioning job done? do you think i should hold off until spring and just work around the problem piping areas? what is a fair price for a replacement central air job, for a 1600 Sq ft house and the basement area cooled from that existing ductwork is roughly 500 SQ ft. thanks for any replies :-)

You have to have a heat loss and AC load did on the home there first. To see just what you need. I am lost as to do you want to take out the heatpump. Or put in a all new heatpump. Id say for sure stay with the heat pump and go with a V/S blower. Get over a seer of 15 there and you can get a $300 tax credit from the IRS