You can add different prices for multiple categories like adult, child, infant etc. for single trip using WP Travel free version. If you are willing to add different prices for multiple categories then you have to add separate pricing option for different category.
To set different prices for different categories like a child, adult, infant, etc., you have to click ‘Add Price’ button under Prices & Dates section.
Also, You can add pricing category by going to Admin Panel > Trips > Pricing Category
For detail assistance regarding adding different prices for multiple categories, please refer screen record.
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