Input from linked page?

Is it possible to bring a certain input to the mailed contact form the page the visitor came from?

For example: On our site we rent out apartments and the visitors should be able to fill out a interest submission for a certain apartment. When that subbmission comes we need to know for which appartment this is for. I see 3 ways of doing this:

1. Create a field for the visitor to fil out which apartment it is for. But that creates more job for them as they might have to go back and look which apartment number they where looking at.
2. Another way is to create a new contact form for every apartment. But thats A LOT of work.
3. But the best way would be to have one “Interest” form and so that the form can bring with it a number/input from which page the visitor came from.

Is the third option possible or do I need to use one of the other? Or might there be another way I haven’t thought about?

Thank you for your help!

https://wordpress.org/plugins/contact-form-7/