The cost to white label an app with only minor branding changes can vary based on several factors, including the complexity of the branding changes and the developer's rates. Generally, since no structural code changes are needed, the cost should be relatively low compared to full app development. For a detailed breakdown of outsourcing app development costs and considerations, I recommend checking out this article: https://www.cleveroad.com/blog/outsource-app-development-cost/. It provides valuable insights into various factors that can influence pricing.