Have an html form that updates a specific Deal

Have an html form that updates a specific Deal

Hi,

We need the ability for a Deal's Contact to update 2 fields in the Deals module.

Can we do this without using Zoho Forms? We cant justify the £7.50pm (Zoho Forms basic package) just so a Deal's Contact can update 2 fields.

Perhaps theres a way programattically to do this using the REST API/Deluge?

Thanks