As with most true BIFL products, you could use the same money to replace a cheap humidifier four to ten times over.
That said, a Dri-Eaz or similar commercial dehumidifier will last forever and can take a room from flooded to bone-dry in a week.
Alternatively you can look into larger non portable units (freestanding or complementary to existing HVAC units) that would in fact be serviceable much like the HVAC system in your home. For this rather than brand shopping I would seek out a reputable installer/service technician in your area and leverage the brand they work with – a good installer/service company means way more than the units brand. Expect in the neighborhood of 1500 and up for something like this.