My parents had good luck with a Mitsubishi single zone system in an apartment they had over the detached garage.  When unoccupied, it had a dehumidification setting so you could let the temp do what ever but keep the humidity (and unwanted growth) under control.  They lived in this apartment full time for two years before starting then finishing the main house.  The unit was first commissioned in 2010 and had zero problems until they sold in 6/22.