You could get something like this

https://s.lazada.com.my/s.1eAK2

It has a knob at both ends that you can adjust to select your preferred weight before you lift. After you're done, you just slot it in.

The cons of this is that you're limited in the weight vs swapping out rubber plates and that the mechanical parts may fail over time though thats more common in a gym because you have multiple users who don't really care about handling the weight properly. For own use, it will last you a while.

bro did you get adjustable dumbell from this seller?
how is the usage so far?

I think if buy the adjustable dumbell with the spinning collars is much cheaper than the Bowflex type of dumbells right?

Just not sure if the bar itself can handle up to 30kg and above without breaking, if we buy the cheap kind of dumbell from Lazada or other place