Exact Time

I'm trying to figure out the best way to configure delivery and pickup times in InflatableOffice.

Currently, our standard delivery time is set to 11:00 AM, and our pickup time is set to 5:00 PM. However, these are not exact appointment times. We typically complete all deliveries before 11:00 AM and begin pickups around 5:00 PM.

What I would like to accomplish is:

• Standard Delivery (No Additional Fee): Customers select their event start and end times, but understand that we schedule deliveries based on our routes. All equipment will normally be delivered before 11:00 AM, with pickups beginning around 5:00 PM.
• Specific Delivery Time (Additional Fee): If a customer needs their equipment delivered or completely set up by a specific time, such as 8:00 AM, they can request that time and pay an additional fee.
• Cart Integration: Ideally, I'd like to add a checkbox or option in the cart where customers can request a specific delivery time. If selected, they would enter their requested time, and the additional fee would be applied to their quote.
• Lead Information: I would also like their requested delivery time to be saved with the lead or reservation so we can see it when scheduling deliveries.

My main question: What is the best way to accomplish this using InflatableOffice's existing features? Would you recommend using custom fields? If so how would i set this up. I do not see cart options on the optional fields Also i do not see it how i can make this mandatory to be selected so no one assumes their chosen time is gauranteed.

I'm trying to keep the booking process simple for customers without having to completely redesign or modify my existing cart/checkout process.