Welcome to the forum. I'm just a little to the west of you in Ok and I have bought five 1999 Boxsters two of which I still have. Good cars to daily. My daughter daily drives one that is over 140k miles and the one that I sort-of daily drive is getting close to 90k miles. I have an '04 S and a 2001 Base that are regular drivers too.
Seningen made a good list of common flaws, but I disagree with his advice to skip the '99s. All years of 986 have some weak points with the engine and ANY 20 year old car is going to carry some risk as a daily driver.
I tend to shy away from 2000 S models because of cracked heads that I've read about on the forum. My 2001 had an engine failure from a broken rod bolt when I bought it. The 2003 and 2004 cars have the highest incidence of IMS failure and it is very hard to find replacement engines for them.
Scared yet? IMHO these problems are nothing more to worry about than the common flaws with any car brand. Personally, I'd rather work on a Porsche 986 than a more recent Chevy or Chrysler. With some care, the cost to maintain is probably the same or better with the 986.
For pricing and market within range of Springdale, take a look at the Dallas Craigslist:
https://dallas.craigslist.org/search/sss?query=boxster&sort=rel
I don't see many in your immediate area and when I do, they seem a little overpriced. TUL and OKC usually have a few for sale on Craigslist.
Great advice here:
https://sites.google.com/site/mikefocke2/mikesporscheboxsterwebpages and Mike still frequents the forum.
My advice: The model year and base or S does not matter too much for a daily driver. At about 20 years old, what matters is how the car was cared for and maintained over the years.