You dont need a multicolor printer .
Use Pause or M0 on the layer to change color
there is a A1 mini slice too.
For the change color :
Be sure to have your layer 0.2 , first layer 0,2 , 100% infill , lines infill
and check the “print thin walls ”
layers 1 to 10 : blue
layers 11 to 14 : white
layers 15 to end : dark
to fix on the wall I use removable nano tape https://amzn.to/3BWPKku
my others design
https://makerworld.com/en/u/2044748376
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