Fillable forms with electronic signature

I run a letting company and we are going from a paper-based agency to a fully fledged online agency without an office and without the need to meet the client face to face anymore. At the moment I need about 6 forms to be fillable and to have various functionalities, depending on the form. The project will start with an easy form and we'll move from there. Overall the forms will need to do the following: - Forms must be shared between users with option to track changes made by various users - Forms should be capable of being locked by user(s) before distribution to final client - Forms to be signed electronically by several parties until main user can lock them (e.g. a contract between company and client filled in by both parties and locked by company before submission for final signature) Note i) Verifiable e-signatures must have a verifiable audit logging, be clearly identifiable to the signatory and be directly related to the document in question Note ii) Signatures should not require users to have an Acrobat Digital ID or indeed any other proprietary software digital ID, as not all users do have these, form should be straightforward to sign by anyone just logged onto the Internet. - Forms to have drop-down lists, text fill-in spaces, numerical fields, checkboxes, radio buttons, flowable Text Fields, and option to add pictures within the form and to attach files at the end of the form, identifying each attachment with a name for each attachment given when added to the form - Forms must be responsive across all operating systems, platforms and devices with various screen sizes and orientations - Forms should be compatible with all browsers - Forms must have a elegant, simple and attractive design, including logo and tag line, header and footer, company details, etc using correct colour codes as provided - Form must have fields reserved for Admin and fields for clients - Form must be exported as PDF as a final product - Form will be hosted on a website for people to: i) Download as fillable PDF, fill in on computer, save and send to a predetermined email address and subject to be the form name together with the signatory's name; ii) Download as a PDF, print and fill in manually and scan and send; iii) Fill in online, submit, then form is saved to the database of our third party software [login to view URL] - Form will have a "Save" button which locks the form, make all fillable fields as "read-only" (so it cannot be edited) and also removes "Save” button from saved sample (not visible on print) Ideally forms must be editable by user without having to purchase proprietary software they were designed with (for change of address, change of logo, etc) - Milestones will be: i) Draft form to be tested ii) Make changes if required and test usability Thank you for reading