City's new ordinances. Can they?

I looked at this deal as a possible acquisition as well.  As a part of my pre-offer due diligence I always do a quick check of any local mobile home ordinances.  Unfortunately this is becoming a necessity due to the anti-mobile home stance more and more cities in Texas are adopting.  It’s easy to check ordinances by visiting Municode Library .  I saw the City’s ordinance prohibiting singlewides in the city limits.  I called Marcy at Development Services to confirm whether or not this applied to mobile home communities.  She confirmed that no singlewides are allowed into the city limits - no exceptions.  It is my understanding that this is why the prior owner on this property started bringing in “modular homes” to fill vacant lots.This difficult ordinance coupled with Bayview’s (Seller) requirement for a super short due diligence period kept me from further pursuing this deal.  I just didn’t see myself having adequate time to sort things out with the City.  Perhaps someone can get the City to grant a variance for this property.  But I don’t see that being granted easily, quickly, nor cheaply.