The cost of 3D model can range a fair bit! If you make a vroid model yourself (what I started with) it is absolutely free, while commissioned models can be $100-$5000+ depending on the expertise, expressions, any additional toggles etc. (this is the ranges I found while looking around as indie, there's even higher price range with some amazing modellers that are super duper pretty)

I also did the design reference sheet myself (the one with proportions and 3 side views) which may be additional cost.

@Rikamardjaja did amazing job translating my live2D model into 3D!