I have no idea
SSI is a federal benefit, many states add a supplement to it.....that chart shows what Maryland 'adds' to the federal benefit. You should check with your state government for the specifics about how to get your home approved. Is your son in a program now ? Fellow parents or staff there shoukd be able to point you in the right direction for help.
There are more knowledgable posters here who work(ed) in the system, but I'm not sure how much they would know about Maryland's specific benefits either.
Best of luck to you !