This is a very good question and the answer has three parts. First, HOA's, are set up per lot as a rule so that each plated lot becomes part of the HOA and pays dues and has a lien against it. Second, you need to review your closing paperwork this should have been disclosed to you and review you HOA covenants. Third, consider contacting a real estate attorney to review your options, a realtor can not give legal advice. I am sorry that you are in this situation and hope it works out for you.
Keller Williams Realty
If you don't like it or think it is unfair, run for the board and get it changed.
If you have enough support you can always try to change the situation.
And anytime you say "Is this legal?" ...You gotta ask an attorney! Other folks, like Realtors, cannot give you legal advice. You need to speak to an attorney who is familiar with HOA's and Real Estate matters, and you probably won't find one on here. These questions are generally answered by Realtors and loan officers.
Try contacting Paula Hester at Alamo Title Company in Colleyville. She is a Board Certified Attorney in Real Estate matters. She can point you in the right direction.
This is an example of the kind of question you ask your Realtor BEFORE you buy a house. Too many people buy a new house without a Realtor, and then they wake up to realize they didn't understand the fine print. Even though a Realtor can't give you legal advice, we do know how to find the answers to questions such as this one, and the time to do it, is before you sign a contract to purchase a home.
Tell all your friends: Never buy a house without a Realtor representing you.
Good luck with the HOA!
ULTRA Real Estate Services