Why limit to Houston? I would do the buying online. Just go to dealer sites. Find one you like and make an offer through the internet. Tell them to only contact you through the e-mail.
When looking at inventory, if the site states In-Stock, then the vehicle is on that dealers site. If it states Available, then it is on another dealers lot. Usually you can get a better price when the vehicle is on the lot of the dealership.
I bought my FJ this way. Made an offer at invoice price and the guy sent back a lower offer. Never met him until I walked in the dealership 50 miles away.