ᐅ Retrofit of Heat Cost Allocators on Radiators

Hello,

In the two-family house (built in 1965) where we own the apartment on the first floor, there is an oil heating system (about 15 years old) with a hot water supply. The radiators do not have heat cost allocators (heat meters/evaporators), and so far, the heating oil costs have simply been split 50/50 between the two parties. Now that the ground floor apartment has been sold, we need a fairer cost allocation. This is also because we no longer live in our apartment ourselves but plan to rent it out.

My questions:

Can anyone tell me approximately how much it costs to retrofit evaporators on radiators? (We have 7 radiators in the apartment plus several in the basement and in the shared areas.)

Which type of evaporators or similar devices would you recommend?

Is it necessary for both parties in the house to retrofit evaporators, or is it sufficient if only we do this for our apartment?

How can consumption for hot water preparation be measured?

Thank you in advance for your feedback.

Thanks,
Elke