How do I attach a ledger board if I have no interior access?
DANGER DANGER DANGER....  As we speak, I am replacing an entire 5 foot knee wall 20 feet long, jacking the floor joists, new studs, mold remediation, new sills, new top plates, new insulation, floor joist sisters, a very expensive 6 foot slider is in jeopardy. This fix is gonna cost my customer over $3,000 minimum  Ants and rot everywhere, all the way to the concrete.  Why you ask?  The deck ledger was lag bolted to the the house through the vinyl siding!!!!   no flashing or Grace ice and water shield under the door or around the ledger, not to speak about invading the water tite integrity of the siding itself. Water seeped in the wall for the last 10 years.  everything in the wall was wet and mold was starting to show on the interior sheetrock. 24 inches is not high. Consider a plan where the deck is free standing and stands a 1/2 inch away from the building, and you will avoid all these potential problems. Seriously, if you don't know how to place a ledger and water proof it completely and then reinstall vinyl siding under the deck and adjacent to it etc., then seek a bit of professional advise or go to a self supporting deck.  simple cross bracing will make a very stable deck not attached to house.