An alternate solution is to export many variations of your models. One with this type of front, another with that shape, etc. To keep it clean and organized, your naming convention could be as follows.
Suppose you have 3 different shaped buildings, each that can have 3 different fronts. The shapes would be called "L", "T", "U", etc. The fronts would be called "chimney", "door", "bare" etc. Your final model name when you export it would be called ABC_bldg_T_door, as an example. Where ABC is your world name and bldg stands for building. It also keeps in tune with pandemics work. I hope this helps!