Schedule B is for interest and dividend income.

Was the rent reduction on their personal residence or a business property?

Rent reduction was for personal property, one time discount of $500 for reference.

Doesn't make any difference whether personal or business, it's income.  Just because they kept it under $600 to avoid issuing a 1099, doesn't matter.  

Thanks. Where do you suggest I declare it.

Thanks, highly appreciate 👍