some 3d models are hard to find?.

Many of us have used external 3d models in our projects. Many sites offer a variety of these, some free, some not. Sometimes we find what we need and then we need to model ourselves.
 
In your work experience, what type of 3d models have been harder to come?. For example ... I have had trouble finding 3d models for wall decoration, playgrounds and kids. What about you?

Regards

What kind of licensing do you require ?  I grab free models from Sketchup 3Dwarehouse, import as SKP into free Shade 10 for Unity 3D, clean up if neccessary, then export as OBJ. Imported into Poser, fix the materials if necessary, and voila. Done.

The Shade 3D step helps convert trigons to 4-gons, but the sensible labelling of materials gets renamed. Works for me.

I need to clarify - Shade 3d for Unity. That's the correct name for it.

I find proper car models the most difficult to find. Very few are accurate or seem to be accurate...

Quote - I find proper car models the most difficult to find. Very few are accurate or seem to be accurate...

Turbosquid has extremely high quality, accurate car models of all types.  Most of the world's most talented modelers sell their works professionally on Turbosquid in between studio projects.

Highly accurate NASCAR model

Great model but a tad expensive for a hobbyist who may only use the model once. The model costs more than a new starter I had to purchase for my 1960 Corvette...LOL

As 3D modellers, this is why we do what we do.  If you need something for a project that isn't available, just model it.

And yes, the $700 basketball at turbosquid (um, that was a few years ago, might be cheaper now).

I am not a professional modeler, for me, it is a hobby.  I worked on this ship a couple of hours a night after work for nearly 4 months.  I might take it back up and build the stuff that goes on the deck.