I didn't buy locally as I couldn't find a store with the selection and competitive pricing I was looking for. You might either buy used down here (like Craigslist) or buy online and have it shipped to your relative's house when you arrive.
I hunt all over this area, never been kicked out...but there are parks I either avoid or keep a low profile around, when I hunt parks (which isn't my main thing).
There is a lot of cool history all over this area. I grew up here and had nooooo idea how much history there is because all you see is the nonstop building cutting down of trees, and covering of land with concrete. It is like our past time around here. But if you do some digging, researching, etc. you will find a lot of history. Pirates, French settlements, explorers (La Salle, Cabeza la Vaca) going back into the 1500's. Not to mention Spanish missions, forts, the Texas Revolution, hundreds of Ghost towns, lost treasures, etc. And there is plenty of 'newer' history around this area as well.
The Humble/Kingwood area is relatively new to our urban sprawl, FYI. Before that it was used mostly for some cotton and other farming as well as cattle. Still LOTS of farm and undeveloped land up that way.
Did you know that George Washington's cousin owned a plantation not far from there, off the Trinity river? Or that there are fossils in the San Jacinto river nearby? And back down southwest of Houston, Santa Anna crossed a river a few miles from my house after his butt whoopin' at the battle of San Jacinto....pretty cool stuff if you are into history, relics, etc.
Plenty of tot lots, beaches, etc of you are into that too.