Hi @John Thi , We are newbies who don't have any deals under our belt yet, but we've lived in Houston most of our lives, so I can share the little bit I know.
Friendswood school district is coveted. Most of the homes in Friendswood are high-end, but there are some neighborhoods with older, smaller homes. The zip there is 77546, but not all of the homes in that school district will go to Friendswood schools.
Spring Branch supposedly has some really good schools (not sure if they are all good). That's the area that's mostly north of I-10 between 610W and Beltway 8 (Sam Houston Parkway). It's also closer in to town, so that's a plus for downtown workers.
There are lots of refineries and chemical plants on the east/southeast side of town (I-10E & Hwy 225), so there is a decent base of people there who are working and have a reasonable paycheck. Those are older areas, and you might be able to find something that would be a good rental property with a bit of rehab.
You can find some decent deals on the south side of Houston (that's where we live and where we're looking for our first deal), but foundation work is very often part of the package. That's our next thing to research....just how much does foundation work cost, anyway?
Speaking of the south side of Houston, keep in mind that all coastal counties (even if the home is in the northernmost part of the county) require windstorm insurance, and it's very pricey. We just payed $1,800 for ours for the year. There is even a part of Harris County that is in the windstorm area. Check the Texas windstorm maps to be sure. Flood insurance is often necessary in the Houston area, even in the non-coastal counties, and it's going up 25% per year right now. Keep us posted on where you decide to focus!