Another vote for Craigslist. I didn't get quite the deal churnman got above, but I bought a 2015 Verve 3 last summer (2016) for $250. The man bought it from the local bike shop, rode it a few times, and then it sat in his garage. The bike didn't have a single mark on it, and it was a $650-700 bike at the time he bought it.
Between the FX and the Verve, it sounds like the Verve might be more inline with what you're looking for. It will have a more upright riding position, and it has an adjustable quill stem, which allows you to adjust it exactly to your liking (you can easily adjust height and angle). The fixed threadless headset of the FX can also be adjusted, but you may have to buy different parts to get it to your liking.
If you consider used, note that the 2016 and previous Verve 2 and 3 used a suspension fork, which may add to your comfort level. Verve 1 has always used a rigid fork, and the 2017 Verve models (all) use a rigid fork. Your local bike shop may have a 2016 Verve in stock with a suspension fork which you could test ride. It'd be good to be able to directly compare one with to one without, to see if it's what you want. Also be sure to find the correct frame size, so if you do end up buying a used bike, you'll know what you're looking for.
To your question, the FX and FX 1 appear to differ only in slight changes in components. The FX comes with a basic quill stem (which you could adjust for height, but not angle) and Shimano Tourney derailleurs (which are Shimano's base-level components). The FX 1 comes with a threadless headset (which may require different parts to adjust to your liking). It has a Shimano Tourney front derailleur, but the rear derailleur is upgraded to a Shimano Altus model. Both use Sunrace freewheels, which is unavoidable at this price point.
The Verve 1 is generally equivalent to the FX 1, though the Verve models say they use an "Alpha Gold" aluminum frame vs. the FX's "Alpha Silver" aluminum frame. What is the real-world difference there? I don't know -- if you do ask this question to your local bike shop, I'd be interested to know what they say. The Verve 1 comes with Bontrager AT-750 wheels (vs. the FX's AT-550 wheels; I'd guess the larger number means a stronger wheel?). The Verve 1 comes with the same Tourney/Altus/Sunrace freewheel drivetrain that the FX 1 has. The Verve 1 (like all Verve models) has the adjustable quill stem.
Both models come with step-through frame options, which I wouldn't overlook, especially if you have limited flexibility. My wife has an older Trek 7100 "WSD" (Women's Specific Design), with a step-through frame, and I think it's kind of fun to ride. It's sort of neat to be able to simply "step through" the frame and then stand on a pedal and get on the saddle. Theoretically, this type of frame suffers less rigidity vs. a traditional geometry, but I don't think that's all that relevant to folks like you and me, who do recreational riding only.
Good luck, and let us know what you buy!