Im writing a custom module that extends the event module functionality.

Now, whenever Someone buys an event booth they get a confirmation mail. 
For every finished booth - instead of having my coworkers call the customer and ask several details, I would like the customer to fill in a digital form that then automatically populates the corresponding even.booth. 
I want to ask the customer questions such as. What type of power voltage do you need, What kind of walls do you need? what kind of carpet do you want etc

I dont know how to do this the best way in odoo. 
One way I thought of would be by somehow using the odoo customer portal (http://ODOODOMAIN/my/home) so that they can sign in on my website and then enter the details on the webpage. However I do not know if that's possible.
(Also it should support multiple events at the same time and customers that are present on multiple events at the same time)

What is the best way to let the customer enter the info?
Can you give me a hint or direction in which way to go?

If the customer portal is the best option:
How can I connect the customers portal with the event booth?
I have already implemented a custom controller /my/booth however I find that writing view for the portal is really inconvenient and im not sure if this is the right path to go down to.

What do you think?
Thank you for your time and tips.