I can answer this:
When you order an REW IDX, you can order it as a standalone (So you can iframe it into multiple sites) or built in (This is where you get all the SEO benefits) but you must choose one or the other when you order it (I highly advise the built in version for many reasons)

So if you have a built in version, you cannot iframe in "just" the IDX, you must iframe in your full site - what we can do, is create a second version of the same IDX (IDX2) or something that has all of the website elements stripped out - this would mean billable time for both design and programming but likely would not equate to having to pay for a whole new IDX

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Strep throat! - Yup tis the season - boooo if you are wondering why you haven't seen me as much it's because I had strep throat for a week, feeling better just playing catch up. Merry Ho Ho folks