Bad appraisal

I was about to purchase an Oakwood manufactured home ( new) and about a half acre to put it on. The cost of the home was 117000.00 and the cost of the land was 35,000. The land prep cost was approximately 50,000 for a total of 209000.00. The dealer asked for a blank check for the lender's records which they then wrote out for 450.00 for an appraisal without my approval. The appraisal we were given was totally bogus. It was done by somone Oakwood has on retainer. The photograph of the property wasn't even our lot. The appraiser certified that he personally went through the house on December 10, however the model home had been sold and moved 4 months prior and was not available for inspection in December. The appraiser wrote a narrative stating that the kitchen and bath in the "subject property" ( the home we hadn't even ordered yet) had been "remodeled within the past 12 months" ! He then proceeded to estimate the worth of the purchase at $266,000 and our loan was to be $265000! this was 56000 over our original loan amount! We found out just in time that the land had failed 2 prior perc tests, thus we canceled the contract. We were refunded the "earnest money" but would like to get our 450.00 back for the appraisal based on the errors in the appraisal. How do we do this?