Well, your in TX so it's definitely hot, so I would sell bottled water. In order to make money at your garage sale, make sure your stuff is organized and looks neat. People will be more apt to stop by and take a look at what you have. Put up signs everywhere. Advertise on craigslist and in your...
I doubt it. A lot of companies will make an offer like that in an effort to try to collect at least some of what is originally owed to them. I have received an offer like that in the past and it was legit.