When you have a real address, use that address in Schema (you can get a Google My Business at this address as well if you own any.)
Where you have used a fake address, leave the address field blank in Schema.
This applies to latitude and longitude as well.
If you give fake data in these, you will see improvement in your rankings. But the fact is that Google is getting smarter day by day and is rolling out updates to its own algorithm. These rankings may disappear FOREVER if you input fake data. That is why we do not recommend our members to input fake data in the fields where you don't have an actual business.
If you have a partner/client and you can do Google postcard verification in that address, then you can use that real data in it.
If you use a common phone number on the page and later plan to change that phone number (when you get more traffic), then don't insert that phone number into Schema, But if that phone number won't be changed for a long time, then you can insert it into Schema.