Just hearing about this case now....
I have some questions:
Suicide. If that was the intent, at a minimum, I'd think she'd overfeed and overwater her dog.... knowing he'd be alone until the daycare dropoff on Friday. But then, Savannah left her beloved pet home, when she set out to commit suicide (allegedly)
No car. Did another CUSTOMER at the car shop notice her? Follow her home? Firsthand knowledge, no car, no housemates. Might even know no cell phone, a detail easily overheard and a topic that could casually arise while filling out paper work at the car place.
Lights on. Door open. Purse gone. Was it DARK OUT when she left?
Smoker. Purse and shoes missing. Dog home. Did she leave to get cigarettes? Was there a convenience store within walking distance? If she left of her own volition, it feels like she intended to be gone most briefly.
Then again, is it possible she walked away from her life? With her shoes, her purse, maybe some stashed cash? Returned to an old life or created a new one?
The mattress and fitted sheet. What might she have kept between her mattresses? Weapon, money, pain medications? If so, did she retrieve it? Or someone else? Pretty specific place for a stranger to look, especially if no other household locations were rifled. Was the sheet used somehow as a wrap for whatever may have been secreted between the mattresses?
Her clothing. Says missing in "her last known clothing" yes? From the Wednesday?
No cell phone, no Internets. Seems like an online angle is completely out. No stalker, no online lover, no secret beau.... unless someone from her past. But no phone history of such a thing so doubtful IMO.
Likewise meeting up with a friend, current or former seems unlikely. Not without phone communication and confirmation.
That leaves, IMO, a random attack, by someone who may inadvertently discovered she'd be home alone, with no car, and no cellphone.
Or a crime of opportunity, if she left her own accord and was abducted from the road.
Praying this case gets some media traction, resulting in really strong tips, so Sandra can be brought home and her children and grandchildren can have answers.