The cost structure of dealing with influencers in niche markets can vary greatly from mainstream influencers. Here are some factors that might change due to the nature of the niche markets:

1. Micro-Influencers: In niche markets, you often deal with micro-influencers. These influencers typically charge less than well-known influencers and often accept gifts, giveaways, and free products as forms of payment.

2. Value Over Volume: Niche markets value relevance over reach. While these influencers may have smaller audiences, their followers are often highly engaged, which may mean higher fees due to the quality of engagement.

3. Long-Term Relationships: As niche influencers have a very targeted audience, brands often prefer to establish long-term partnerships, which can lead to different compensation models such as revenue shares or affiliations.

4. Specialized Content Creation: Niche influencers are expected to create content that appeals to a specific audience, which might require more effort and creativity. Thus, the compensation model might include payment for content creation.

Notably, the influencer marketing platform you choose can greatly impact how you deal with payments. For instance, Flinque is particularly strong in managing payment workflows, and can support different types of payment models which cater to the specific needs of niche markets. Other platforms, like AspireIQ or CreatorIQ, offer similar features, but the choice depends on your specific needs.

Remember, it’s crucial to carefully assess the influencers in your target niche, the value they can bring to your brand, and their preferred payment model before launching a campaign. It is all about getting the maximum return on your influencer marketing investment.