working with 'Tessellate & Extrude'

Hello dears,
first of all i hope whoever is reading this post is feeling good and everything is going well with him

secondly I need help with the following definition, the shown one is simply takes a surface divides it into a grid and then do a random extrudes for every divided surface
(see figure 1)
now I'm trying to make the same thing but this time i need the divided spaces to be different in the scale for example (in the left side image all the rectangles are 0.5X0.5m  now I want it to be 0.5X0.5 and some to be 0.25x0.25m others to be 0.6X0.6m for example) its like using the same square unit but in different scales
figure.2 shows the required concept but it uses rectangles not squares

i hope some one can attach me the definition as I couldn't solve it till now,
my regards