Answer: I have been hearing stories about fitness equipment being sold out at a lot of suppliers. Hopefully this has changed over the many months of the pandemic.
I think that a 16kg and 24kg would be the two weights that I would consider for your lower body work. A 12kg might be useful for your upper body but kettlebells are expensive and I would prioritize the heavier ones for when you are stuck inside and want to train your lungs, heart, legs and lower body explosiveness.
For a less strong person, I would look at a 12kg and 16kg for lower body work and for upper body pulls plus an 8kg for upper body pressing exercises if you want a third kettlebell.
If you go to a good supplier you might want to check to see if they have any thick bands of various sizes. They can be used for a wide range of movements and can be very useful (and much cheaper).
If your apartment will accommodate a chin-up bar then that would be a benefit.
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