Maya and Unity have a 1:1 scale ratio, which is in Meters. A 1x1x1 meter cube in Maya is equal to a 1x1x1 cube in Unity. However, Unity imports models at a 0.01 scale. Import Scale can be changed in the Import Settings in the Inspector.
Try to keep the model’s polygon count under 6000 triangles (see Figure 1)
Fig. 1, Polycount
. For a frame of reference: Half-Life 2 characters had 2500-3000 triangles.
Use 3 and 4 sided polygons. Unity will automatically convert 4-sided polygons into triangles but anything over 4-sides will cause unpredictable results.
Watch out for backface culling. In a game engine, usually only the front side of a face is rendered, to save on processing power. This means that if your model has a funny issue in Unity where you’re looking at the inside of a model, it might mean your faces are pointing in the wrong direction.