AYes, you need an active opt-in from the customer in order to be allowed to contact him/her using WhatsApp Business. You can, for example, add a checkbox on your website for the customer to opt-in. Alternatively, your customer may also initiate a conversation with your company on WhatsApp.

A Additional to Libromi Connect package pricing there will be a usage based bills you have to directly pay to Meta (Facebook). In UAE for a business initiated conversation it will cost AED 0.11 for a 24 hour window, and if it is a user initiated conversation it will be charged AED 0.065. All the messages inside the 24 hour window will be free.
WhatsApp is considered a premium channel offering rich media notifications, thus prices are higher than SMS

A
 You need a registered business with address proof and phone number proof to get verified with the Facebook. and the basic details like Facebook page and a reserved phone number only for WhatsApp Cloud API

A

WhatsApp supports user-initiated and business-initiated messaging. With user-initiated messaging, the first message is received by the business from the user. This opens a conversation in which the business can reply back with free-form messages. The conversation remains open for 24 hours following the last message received from the user.

Business-initiated messaging is when the business sends the first message to the user, or replies to the user more than 24-hours after the last message received from the user. This typically applies to notification use cases. Business-initiated messaging requires the use of pre-approved templates.

AYes, but you need to delete the whatsApp account. After you deleting the WhatsApp conversation there is currently no option to migrate the old messages to WhatsApp Cloud API.

AYes, You can stop the subscription anytime with exist procedures, We will provide required credentials to move to a different service provider .

ALink to Facebook hosted document