He wouldn't get more money for living on his own. If Barb died, he’d potentially get some of her money (assuming she paid into it and wasn’t just mooching off Bob), but even then, they only let a household have a certain amount.
He got more when Bob died because he was considered a disabled adult child who was disabled before age 22, so he got a certain amount of Bob's benefits. Also, remember, Chris can't earn more than a certain amount a month without losing SSDI benefits.
Now, the question is, could Chris find a place to rent to him for within his tugboat? Possibly? A quick perusal of options in the Charlottesville area shows that there are definitely sub $800 a month options. He'd still need to pay for utilities and internet (internet would be discounted for being a tard, mobile phone service too), food, and some sort of transportation. So it would he rough. There would also be the issue of finding someone to rent to him since he wouldn’t fit a lot of income requirements. Again, low-income housing does exist for this reason, but it can be hard to get access to and isn’t guaranteed. This is usually why people like Chris wind up relying on family members forever. And why when retired people are widowed, they often have a hard time if they didn't have significant savings.
My parents were worried about how a friend of theirs was going to keep his house, even though it was paid off, after his wife died. The couple had been stupid with their money (mostly by supporting one of their degenerate sons) and the man's SSI stuff wasn’t going to be enough to cover his bills and property taxes. Losing her monthly income, which was not as much as his, so he didn’t get any of it (or much of it), really put him in a bind. If he’d died first, it would have been totally different. We thought he'd have to sell his house and move into a small apartment at 70. Fortunately, they had a second property that was paid off that sold for a lot more than expected so he's fine for the next ten years or so, albeit on a fixed income.
This is why I’m confident that his lawyer is trying to get him into a group home or facility, even if only for the short term. It’s really the only option for him.
If Chris hadn't decided to rape his mom, he could continue to subsist off of her. He'd inherit the house when she died (he'd probably still lose it, but that’s neither here nor there) and probably get some of her tugboat. Plus, he'd have the aunt and uncle to watch over him and throw him a bone every now and then. But since he had to fuck his mom, he can't go back there. It’s unclear if he'd even get the house or not (Barb or the relatives could change the will) — or if the house will even exist by the time he's out (if Barb was forced into a nursing home, the state only pays if you are totally broke. Meaning, they'd sell that shitty house and then use the meager proceeds to pay her nursing home bill until she was broke), and Aunt Harriet or whoever sure as shit will never talk to him again.
He had a good thing going. He fucked it up.