Is it safe to use third party Dynamic DNS services for IPCam?

Question

CCTV

Hello!
I want to buy an IP WiFi camera with 4G traffic. A dynamic IP address is issued there, i.e. you need to somehow "fasten" the dynamic DNS so that the interface always has the current IP, the one that the 4G provider currently issued.
I know about services like dyndns, no-ip, but how stable are they?
For example, in my router settings there is a Dynamic DNS option, there are such services to choose from:

But dhs.com does not work, tzo.com and dyndns.org redirect to dyn.com, which only offers a trial or tariffs for $5/$40 per month .
How do experienced CCTV installers deal with this issue? After all, if they put a client, say, a WiFi surveillance camera with tzo.com, dhs.com or another Dynamic DNS service, and when it "falls off" - there will be a wave of complaints and a lot of work, penalties.
Raise their own Dynamic DNS on the server?
Is it possible to make such a dynamic DNS at low cost and reliably without worrying that after some time the service may stop working and you will have to go into the settings?
Thank you!

Answer 1

DDNS does not work through NAT, external address costs money for operators, traffic is considered per megabyte. Some comrades fly about 2k per day.
So mikrotik and vpn are our everything. For such purposes, I keep routeros on vds, for a moderate fee I hook clients. The thing is not about making money, but about customer retention. Reason for calling once a month, clients bring new objects. In general, I recommend to think.