Is air-con just that rare? A heat-pump isn’t all that much complicated than a ducted air-con. Here in the US, most HVAC service companies can/will service all types (pure AC, heat pumps, various furnaces, etc).
Mean daily maximum in July and August in Utrecht is 23C/73F (compare to 30C/85F in Chicago and NYC). The Netherlands is further north and a lot more moderated by ocean temperatures - it's kind of like SF in that regard except the entire country has a similar climate so AC is not a cultural expectation.