Installation of wireless water meter: Replacing apartment water meter

Hello,
I have an (old) rental building where I need to replace the warm and cold water as well as heating meters for three parties. The verification period has expired.
Since from 2026 only radio-based meters are allowed, I want/must install exactly those.
What surprises me is that there is almost no information around this topic. Even my plumbing company has no idea how the connection of radio-based meters works and what to pay attention to.

The meters currently installed with me (cold/warm water) are Lorenz measuring capsule meters IST with QN 2.5. The new meters must therefore fit the existing base. I have obtained an offer from Lorenz. Now I have to fill out a configuration file. For this I have the following questions:

1.) The meters communicate based on the OMS "standard". But which radio mode must I choose and what are the implications?

2.) Furthermore, I have to specify the telegram type. What is sensible to select here and why?

3.) As a default setting, I have to choose between these three options. I still understand Walk-by. But what do the other two mean?

4.) When I have installed the radio-based meters, I will also need a gateway to collect and send me the data. This must be able to capture the data from the meters. Which device can you recommend and what do I have to pay attention to here?

5.) I have the impression that the topic of radio technology has not really arrived in the plumbing sector yet. I fear that I will buy expensive devices, have a lot of effort, and in the end, nothing will work.
There are also meter service providers. They offer meter replacement, reading, and billing associated with it. If I use a service provider, then the heat meter for the heating and smoke detectors should be taken over at the same time. Do you have experience with this and can give me recommendations?

Many thanks for the support!

5.) I have the impression that wireless technology has not really arrived in the plumbing sector yet. I fear that I will buy expensive devices, have a lot of effort, and in the end, none of it will work.

Yes, that's how it is. Currently, no one is seriously taking care of it.

There are also metering service providers. They offer meter replacement, reading, and therefore billing creation. If I hire a service provider, then the heat meter for the heating and the smoke detectors should also be taken care of. Do you have experience with this and can you give me recommendations?

Since the costs for this are mainly borne by the tenants, I would always rely on this for multi-family houses. You can take one of the big providers like Kalo/ista/techem, etc. or regional small companies. There are even listings sorted by postal codes on the internet. Just have a look – links are not allowed to be posted here.