If you want to change part of the lease, discuss it with the landlord. If the landlord agrees, the two of you should decide how you want to word the change and then write it into the agreement. Both you and the landlord should then initial the change. For example, many standard leases prohibit pets, but your landlord may be willing to accept a pet if you put down extra money as security.
Peace and Quiet
Your rights as a tenant include the right to "quiet enjoyment," a legal term. This means your landlord cannot evict you without cause or otherwise disturb your right to live in peace and quiet.
If other tenants in your building are disturbing you, you should complain to the landlord. Of course, you may not disturb other tenants either.
Except under certain circumstances and subject to certain conditions, a landlord may not interrupt utilities to a tenant unless the interruption results from bona fide repairs, construction, or an emergency. See Tex. Prop. Code Ann., § 92.008.
Health and Safety
You have a right to demand that the landlord repair any condition that materially affects your physical health or safety. § 92.052.
Justices of the peace have authority to order landlords to repair or remedy conditions affecting a tenant's physical health or safety, as long as the cost of the repair does not exceed $10,000. Tenants can go to justice court without an attorney to obtain a repair order. § 92.0563.
Unless the need for repair was created by “normal wear and tear,” the landlord does not have a duty to repair problems caused by you, another lawful occupant, a member of your household, or your guests. § 92.052. Under certain conditions, you and the landlord may have a written agreement that you will make needed repairs.