I'm currently in the process of house hacking my first investment property. I'm trying to use FHA to put down the least amount possible.

My appraisal came back and everything was good except for the Self Sufficiency rule. 

The appraiser is quoting estimated rents for my property pretty low, even when looking at HUD as well as the comps the appraiser used.

I have a 3 family. Each until is 1675 sqft with 4BR, 1B. He is estimating rents for each unit at $1850/m. 

When looking at fair market value in my zip code on HUD, 4BR are $1932 for 2022, jumping to $2,255 next year.

I'm also very confused because ALL of the comparable rentals he used in his report are getting higher monthly rents than what he quoted for mine. 

The comps he used for 4BR range from $1900-$2100/m. A 3BR getting $1965/m. 

They ALL have less square footage and some less bedrooms. All other data is the same, as far as building condition, area/neighborhood etc. 
The only comp that matches my estimate at $1850 is a 3BR 1 bath at 967 sqft. Again, my units are 4BR 1 bath at 1675 sqft. 

This will force me to put down $138,000 instead of around $28,000! 

I am being told there is "nothing that can be done" Despite my loan officer and real estate agent trying to get adjustments. 

Does anyone know if I can file a dispute, or should I get in contact with a lawyer? I feel like the appraisers estimate isn't making much sense and he is not willing to discuss it or explain it in more detail. 

Thanks!!