I will be blunt: this is the single most important document your LLC will ever have, and skipping it because you are friends is exactly the scenario that leads to destroyed friendships and expensive litigation. I have seen it dozens of times.
An operating agreement covers things you have not thought about yet. What happens if one of you wants to leave the business? What if one of you gets divorced and your spouse claims a share of the LLC? What if one of you stops showing up to work but still expects 50% of profits? What if you disagree on a major business decision and you are deadlocked at 50/50? What if one of you dies?
Without an operating agreement, Texas default LLC law under the Texas Business Organizations Code governs all of these scenarios. Those defaults may not be what you want. For example, under default Texas rules, a member can transfer their economic interest to a third party. Do you want your partner’s ex-wife to become your business partner?
The $1,200 is money well spent. If that is too much right now, there are online templates for $200–$400 that cover the basics. But please do not operate a multi-member LLC without a written agreement. I cannot stress this enough.