If it were me, and I wasn't going to have a car, i'd get as close as I could to work. It's going to cost more, but you might make it up in less ubering and stuff during the week.
This complex is what I would consider walking distance. There's some retail not far as well. I don't live around there, but I work in Las Colinas, and lunch in that area a lot. I don't know what kind of bus routes are around, but I wouldn't want to rely on them all the time. I don't know your comfort level with walking around at night either. Male, female, amateur MMA fighter? Las Colinas isn't rough at all, but everyone is different.
You'd also be pretty close to DART and you could take that all the way to downtown Dallas. I'm guessing there are stops pretty close some decent nightlife.
If you don't have a car I don't see how renting a room from someone is going to work. No one is going to be that close to the office for you. And probably not close to mass transport either. and even then you'd be doing bus->rail->bus to the office. Personally, I wouldn't want to do that every day. You'd cost yourself 2-3 hours/day in travel time.