Be cautious about the vent filters. If you forget to clean the filter, it could result in a fire. I would rather reroute the vent to another wall and punch thru it. It will be a bit more work, but will be safer. Also, stay away from the plastic vent hose as they also contribute to house fires as well.
Also, I once moved the air unit, and it was not that big of a job. You should have an air conditioning expert come over and let him give you his opinion on the cheaper option.