There are restaurants out there that are non-chain, mom-and-pop restaurants that really aren't like the one you listed. Doesn't mean she's going to be high maintenance.
You need to get out more dude. These posts in this thread and the posts in the boyfriend getting beat up by his gf thread are not a good look for you.
Although I will say I understand your reasoning when it comes to not spending a lot when it comes to a chick I may never see again. All I'm saying is there are non-chain restaurants that won't break the bank.
This is in downtown Houston:
Just found it on yelp. Has 4.75 stars and has only one "$" sign indicating it's not expensive. Shit I'm sure there's tons of decent mexican food that isn't taco bell that's not expensive.