Expo Client Interaction & Automated Quoting Portal

I am looking at building a portal - we will be giving the clients at an expo a ipad to complete there requirements (pick and chose the products they want)
- add there information
- add there mobile number and email address
- Add there requirements which is usually up to 10-20 items
- we then want this portal to automatically add the items up and give them a price to buy now or to buy after the event
- we then want the system to send the client an sms with the cost so they have it - they can either accept quote or reject quote
- if accepted they - we want it to take them to a deposit page to make a deposit
- if rejected we want the system to send follow up sms and emails till they opt out

Backend: We can adjust pricing according to the state we are working in
We can apply a discount if needed
we can see all the data and have updates on each expo we attended and who completed the form who accepted or opted out and who will remain to get a follow up from us
this is where all products items are stored with us being able to add, adjust or delete a product (keeping in mind we go to expos to gather this data and the quoting system will streamline the human activity)
We would like it to run some stats for each event so we can see total entries, sold jobs, not sold

Other features: As guests enter the information we want to be easy and quick please make suggestions here. The system can remind them of us by sending out emails which allows them to follow us on instagram, our next expo we will be doing in that state - etc
they can also request a zoom meeting - if they want to discuss the final details before they proceed.