WordPress Checkout Enhancement - Touring Luggage Options

For my WordPress website I want to add model-specific touring luggage add-on to my checkout system for a flat NT$1,000 fee per rental. ​We need a custom option during checkout to display specific luggage dimensions based on which bike the customer chooses... (Budget: $30 - $250 USD, Jobs: HTML, JavaScript, MySQL, PHP, Web Development, Website Optimization, WooCommerce, WordPress)