Can't Progress Past Challenge Task 1 of 4 - Unsure of what fields the result dataset should contain...

In the Challenge description of Challenge Task 1, it asks to return all Model Names (Model.ModelName) for cars for Sticker Prices (Car.StickerPrice) over $30,000. Using the knowledge I have about the JOIN and WHERE <field> IN (<subquery>) clauses, I wrote the following SQL Statement: SELECT Model.ModelName FROM Model OUTER LEFT JOIN Car ON Model.ModelID = Car.ModelID WHERE Car.StickerPrice IN (SELECT StickerPrice FROM Car WHERE StickerPrice > 30000);

Not only does this return duplicative models in the result set, I get the error "The subquery doesn't return all ModelIDs for cars with the sticker price greater than 30000." The error statement suggests that I should return ModelIDs in lieu of Model Names, so I revised my query to state: SELECT Model.ModelID FROM Model OUTER LEFT JOIN Car ON Model.ModelID = Car.ModelID WHERE Car.StickerPrice IN (SELECT StickerPrice FROM Car WHERE StickerPrice > 30000);

After submitting this answer, I got the same error statement. At this point, I am not sure what Challenge Task is looking for. There does not appear to be any fault in my WHERE <field1> IN (SELECT <field1> ...) criteria. Adding the field "Car.StickerPrice" to the SELECT clause of my main query suggests that no results equal to or under $30,000 are returned. Also, changing my JOIN clause from "OUTER LEFT" to "INNER" does not seem to change the results, even when selecting only the ModelID or ModelName field from the Model table in an attempt to limit duplicate values.

It seems I've tried every combination of fields in my SELECT statement to try and satisfy the Challenge Task's requirements, but to no avail. Is there in error in my WHERE clause,, or is the Challenge Task looking for a specific field in my result set, or could it be that there is a glitch/error in the code that is preventing me from progressing forward?