I am also modeller, and I have made a lot of models including 3d prints, figures, clay models etc. And I know how to prepare a model for 3d print, and solve the printing problems before they occur :)
Relevant Skills and Experience
I am good at 3d modeling in not just architecture but in other forms, so I am capable of modelling and adding the additions you want. Also I will make them solid mesh and optimize it for printing.
Proposed Milestones
€8 EUR - I will model the parts you wanted as draft until you like them
€11 EUR - I will add details and make them printable solid mesh