For example, if one of the tenants gets $1000 a month in Social Security Disability, I would feel a lot more security than if she made the same $1000 by going to the day labor place.Based on everything you have said, I'd just stick to my guns and ignore the complaints.

They're both 62 year old with fixed pensions and about to be eligible for social security. 

You can find a lot out about someone through Social Media now a days...

Also, don't overlook using social media (Facebook, Twitter, LinkedIn, Pinterest, Instagram, etc.) to find property owners.

Especially for a young person hoping to be close to a good social scene?

Do you know how it works out if I don't want to terminate the tenancy but just not participate with the S8 due to not being able to provide some of the information requested like my social security card?

I also tried https://www.rentecdirect.com/ they had a GREAT tenant finder that found your tenants online presence (social media profile), I wasn't keen on the software other then the tenant locator side! 

Socially, they are seen as established people, able to buy a place for themselves.

The pension along with social security will amount to roughly $70k/year. 

Nothing like a helicopter parent to lay waste to the social cohesion of the housemates.If you have them as a guarantor for the obligations of their charge, they have the right to be kept aware of the fiscal wellness of the lease and the obligation to open their wallet should little Johnny or Jenny fail to perform.