Poser vendors have 2 main problems:

1. Not knowing which Poser figure to use

There's a bigger market for Genesis 8 and Genesis 9 than there are for the Poser characters. 

I don't think there has ever been universal adoption of any Poser character by the Poser community since V4. They've all been a little hit and miss. And as Crystalis mentioned, you need to pay for the Poser characters, whereas the base Genesis characters are free and come with enough content to create a promo image. So in my position as a content creator, I don't own the "paid" Poser characters, and I don't know which free Poser characters are popular enough to create content for - so I just don't create content for Poser characters. It's too risky - you can spend two weeks creating something and have 1 sale.  

I don't have any stats on how popular La Femme 2 is - but she's too expensive for me to risk buying her - I won't get my money back. And I wouldn't use her for any reason other than content creation.

2. Daz is easier

Daz has developed systems and features for content creation. They can show 2-sided meshes, and it's easy to parent props and collapse a series of parented props. 

Daz auto exports the geometry files - you still need to do that manually in Poser.

Daz has an option not to overwrite thumbnails. Poser does not have that option.

Poser has a massive bug with their drag and drop feature (it doesn't disable) so I'm forever frustrated by my screen being dragged somewhere  - and I never want it to drag anywhere. I have no issues with Daz.

So to re-ignite the Poser market I would say you'd need to:

1. Offer vendors free upgrades on Poser software.

2. Give vendors the main characters for free.

3. Talk to the Poser development team to make things easier for vendors.

4. Talk to Poser customers and find out what they want - then tell the vendors.

5. Increase Poser's market share by promoting the software (For example, I wrote an article here on why game developers should use Poser (or Daz) and not AI - but it's published here and not on game development sites.)

As to the "how much" question - that depends where the vendor lives. Dollars go a lot further in Africa and South America than they do in USA and Europe.

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