Heating/Qualm from the heater/ nice estimate from 🙂

Hello people, please ask for your advice. I have already searched the many heating/coating topics and also Elchwiki. However, the following problem arises with my S60: the vehicle already had the heating function when buying it. Nevertheless, at lower temperatures, it smokes violently from the engine room. Thanks to forum my suspicion was on the heater. The 🙂 the problem was described, today I got an estimate of almost Eur 240,- fue Now my questions: 1) if the heater is already “drin” or has been activated, why is there still the problem with the heater? 2) Who had/has the same problem – and above all: are Eur 240,- justified (for what?)? I find this amount very heavy for a problem known to Volvo. 3) do I correctly assume that there is only one solution, namely the deactivation of the heater? In other words, in order to avoid short distances. To get warm air in the morning, do I have to activate the timer of the Stanheizung every time? Thank you for your inputs.