Has anyone ever needed the statement of non-availability?

It's $290 a day max with the station per diem/M&IE separate from the hotel right? If I read the reg right (not sure it was clear in my finance brief) it would look like this for member + 3 dependents (2 under 12).

150% X M&IE + hotel must < or = $290

I've never actually figured it out before, but got curious today.

Not sure on your numbers or cost stuff, but I took TLE moving out to Camp Pendleton and I had to show Admin the statement of non-availability from the base hotel and BOQ/transient quarters. We took all ten days and I think the hotel just had to be a GOV rate. Pretty sure we didn't get per diem.
Different services might have different regs (this was also 6 years ago, so it's a little fuzzy).

It's as joint travel regulation...and the way I read the reg is that it will be the lesser of the two 290 or the hotel rate at which you stayed minus the per diem. Thus, you don't have to stay at a military rate...that is what I want to clear up.

Read these FAQs and see if any of them answer your question:
http://www.defensetravel.dod.mil/site/faqtle.cfm