Fun and affordable compact/midsize

High mileage VWs are money pits. The problem is the way the engines are designed replacing things like vacuum lines (which disintegrate on those things leading to check engine lights) require massive disassembly to get to the various bits. almost everything you do in a jetta or gti will require removal of the bumper and front assembly... just the way the engines are put together.

Saabs are (the ones that are subarus under a different badge) are fine, but other saabs are expensive due to parts costs.

If you want something fun to drive and reliable think about the mazda 3 hatchbacks, and the mazda 6 sedans.

I can tell you from owning a Saab 9-3 from 2006 to 2018 (until a week ago when a tree literally fell on me) that they can be reliable, particularly the 2006 model year. I had 170,000 of mostly troublefree driving and it never left me stranded (until the tree nearly fell on me, I had to drive off the road, and I broke my radiator, oil pan, subframe, and one tire/tire rim costing too much to fix). The car was worth $3000 so with over $3500 in repairs I had to say goodbye to it.

It was fun to drive as you mention and it got very good gas mileage, I averaged 26 mpg on regular fuel in a mix of city and highway driving. Parts have gone down in price as Saab USA wants to keep them on the road as long as possible. As a result, it actually cost less to fix as the car aged.

So, what went wrong over 12 years? I had to replace a faulty alternator at 70,000 miles (it never failed, it just did not work correctly). Cost $300 to replace. Had to replace a driver seat bolster at 130,000 for $280. Had to replace the AC compressor at 155,000 for $400. Had to replace a leaking power steering pump for $250 at 160,000. That was it. So more repairs near the end but nothing major, and nothing outrageous in cost.

The VW unfortuately does not hold up as well today but old ones are great. I owned one back in the 1990s. A 1994 VW Fox which was simple and easy to fix, so I worked on it myself. It had a bad clutch when I bought it used so I replaced it. Also the AC did not work when I bought it so I discovered when a new battery had been put in (I asked when it broke, and they said when they bought a new battery) and I removed it, they crushed a vaccum tube and a plastic valve. The plastic valve cost $1.50 and a new vaccum tube cost $2.00. I got $1000 off the price for no AC and it cost me $3.50 to fix. That was when everything was manual (stick shift, no power steering, no power windows or locks... you get the picture). Those manual cars were fun to drive, and were durable. However today as VW has gone electronic their reliablity has gone downhill, so you take your chances with them now.

Mazda 3 is more reliable than either, and they are okay to drive (better than the average sedan) but not as good as either the VW or Saab you are considering to drive.