Finding Real Work, With Support

My adult child [Initials] ([Their Disability]) wants a job. What they're good at: [What They're Good At]. What they'd struggle with: [What They'd Struggle With]. What we've tried: [What You've Tried]. Where we live: [Your State]. Help me: 1) explain in plain language the difference between supported employment, a sheltered workshop, customized employment, and a day program with 'vocational' in the name — and which fits [Initials], 2) tell me who typically pays for job coaching (vocational rehabilitation, the Medicaid waiver, both) and what to ask each one, 3) give me 8 questions to ask an employment agency, and what a good answer sounds like, 4) suggest three kinds of jobs that match the strengths I listed — real jobs, not the same three everyone suggests, 5) tell me how work affects SSI/SSDI in general terms and who to ask about the specifics before they start. Not legal or benefits advice — tell me who to call for that.