If you are selling products that are expensive, you cannot close it through one phone call or using a shopping cart system.
You need to fix an appointment for you to do sales demonstration to judge the customer level of interest and the percentage of closing.
Before that, you need to arrange an appointment with the client and most of them will find excuses to drop the subject or end your call.
The traditional of telemarketing sales speech is 98% proven failure in my point of view.
What you should do is to take RISK, you inform the client what you want to sell and let them know you will provide a free service to show them your product. If they are interested they take it or else no obligation.
You need to challenge them to give you opportunity to meet u. By doing so, talk to them as if they are your long lost friend and handle objection wisely.
In this tactic, do not confirm anything or explain much about your product, you only highlight and offer explanation until appointment is made.
Note: make sure you say something to make them interested and yet don’t give a full detail answer.