I am in the midst of engaging IDs as well. I have approached 5 so far and 3 have done site visits. For the first appointment, we went their office to discuss the layout plan and bounce off ideas, second appointment is to go to the site and third appointment is the delivery of quotes. Is your unit a resale? Might need to highlight when sending over the floor plan as in most cases for resale, the floor plan would not reflect the actual unit.
If you want to know the 3 who have done site visits before quote, can PM me and I can share with you. We have not engage any of them yet, still in the midst of gathering quotes.