Looking for feedback from someone who has done this, mainly just to confirm that my guestimates are not way off.  I know enough to be dangerous not my area of expertise.

Trying to budget for a custom 3D skeletal animation system with cross fading and 2 layer blending.  Context is Unity.

My thought is someone who has done it before could probably get the core features working in some form in a month.  But by the time you factor in everything like bugs, performance refactors, platform specific gotcha's, whatever, it's probably around a 6 month job to get something actually usable in game.

Does that sound reasonable?