Some Appraisals are unqualified and do evaluate properly

[Bennie Leija]

I am a builder investor out of the Houston area. 
We went out and pulled two appraisals, one by me and didn’t share in the beginning because I didn’t want my appraisal to be bias. The clients bank (buyer) went out and appraised the house. Their appraisal appraised $90,000 less compared to mine. 
I want to know what can be done in this circumstance as the banks representative stated that my documents are false and forged. I was told to hire another appraisal but as I sit here looking at my accounts, if I accept the offer of $90,000 can I report this as a loss to the IRS? This build took me over 5 months and I basically have done the work for free. 
Is the market having a negative impact on your business as not getting true and better figures?

Enjoy your day

Bennie