The reason for my question is to see if you can give me an idea (similar or not) or know of any type of software/web app available for the following that I am going to tell you.
The context
My sister works in the healthcare industry and currently manually handles several different spreadsheets (Google sheets) in a way for her customers and incomes.
My idea
He had thought of an online form for income. This form would have, among others, a field for the customer's name that would be automatically filled in from the customer's spreadsheet as it is searched while typing. If it exists, other fields on the form will also be filled in automatically. If it doesn't exist, once the revenue-related data is populated and submitted, a trigger would update the new customer data in the customers spreadsheet so that the next time the form is used, the field customer name can be auto-completed with the updated customers.
My solution
I have tried a lot of online forms and softwares: Jotform, Caspio, Logiforms, Typeform, Gravity Forms, Formsite, Quinta DB, Airtable, Rest.io, Ninox, Podio, Cognito Forms, Matrify, Zoho ... but without full success.
For this purpose, the only ones that fit us are JotForm (it would be semi automatic since it does not automatically link spreadsheets), Caspio (it is perfect but excessively expensive for us, € 200, since the basic plan does not include triggers), Logiforms ( its trial is very limited and we cannot test if it would really work for us)
I tell you all this to ask for your help and to ask you if you know of any other software, web app, solution or even think of another different workaround to forms that I have not thought of and can help us.
Thank you very much for everything and a hug.