It is hard to give a full opinion without knowing where you live. Cost of tests will depend on a number of things- location/state, type of test, etc.
Personally, I don't like the "short IQ" tests because I think they are more likely to miss stuff...
In my area a full iq test (WISC-iv or Stanford Binet) costs between $ 300 to $400 USD. A full psychoeducational asssessment costs a lot more--- 2000 usd.