We are going the grad school testing route, too. (Haven't done it yet, but just spoke with them on the phone to get the details.) Just to give you an idea, our state university charges a $500 flat rate for IQ, achievement and developmental testing. If they uncover any issues that point to the need for further tests, those are included in the flat rate. They give a full written report which is co-signed by the grad student tester and their supervisor, who is a licensed psychologist. I found the info by looking on the University's website. I tried psych departments and education departments and eventually found it.

Every other place we looked was $1500-2000 for the same tests and any additional tests were an additional fee.

Hopefully it will be a good experience. Fingers crossed...