I passed on a Specialized Roubaix that just needs too much work.
I searched for a Roubaix wanting a bike with more endurance frame geometry.
I found an ad for a Fuji Roubaix 1.3 that is in very good condition.
Does anyone here have one or had one? What do you think about yhem?

Check the Bikepedia database. That should you narrow it down then you can Google reviews for the specific model & year.

BikePedia

Stack is lower on the Fuji by 43 mm on the 2018 Fuji Roubaix and 2021 Spesh Roubaix that I compared. So it will be a more aggressive fit unless this is a year model they had a different geometry on.

Learn how to read the geometry numbers for the bikes and you can answer this question easily yourself.

This bike doesn’t have disc brakes so it may be 2015 or a little earlier.
I am wanting a more upright position than the race position.
I haven’r read anything bad about Fuji. They seem to be a solid, reliable sorta dull bike.

Looking up the 2015 shows a 598mm stack height.

It's all relative to other stuff. However generally looking at the same effective top tube length, a bike with less stack than another will be more aggressive in fit than the other. You can go by the stated frame size, but then what do you do when one is S, M or L and the other CM sizes?

Frame stack will be different even among the same model of bike as a different times the mfr will alter the geometry slightly. Sometimes you can just go to the next larger frame size and get your stack higher to allow you a less aggressive position. But that doesn't work for everyone every time.

So if you are wanting to know whether a bikes fit is aggressive or relaxed, you need to either try it on, or compare the exact year and model of the bikes specs with the other.

The Roubaix as far as I recall is Fuiji's race frame, not its endurance frame (https://www.cyclingweekly.com/review...ji-roubaix-1-1 Fuji Bikes | 2019 Roubaix 1.5 | Bike Archives)

Fuiji makes the Sportif (https://www.fujibikes.com/usa/bikes/...ortif-1-1-disc) and the Gran Fondo (https://www.fujibikes.com/usa/bikes/...gran-fondo-1-1) as endurance models.The Roubaix (2019) has a stack height of 579 and a reach of 403.

The Gran Fondo (2021) lists a stack of 602 and a reach of 376 for the XL frame.

Pretty obviously the Roubaix rides lower and longer.

I recommend the Sportif as an endurance frame .... I have a 2017 model and I find it quite comfortable.

I haven’t sat on it. The seller just replied he thinks it’s a 2013 model, but he doesn’t ride. He is a reseller so I won’t get a lot of info.

Were you not the poster who was getting back into cycling riding his father's old aluminum whatever which you didn't like, and because you had developed an aerobelly, you wanted a more upright bike?

Please visit the sites I included. You will see this : "Though it may share its ‘Roubaix’ name with a series of carbon-fibre bikes from Specialized (which, incidentally, licenses the name from Fuji), it couldn’t be more different. Fuji places its Roubaix in its ‘road race’ series, and so the bike has a slightly more aggressive stance than more relaxed leisure-bound bikes." (https://www.cyclingweekly.com/review...ji-roubaix-1-1)

People are trying to help you. let them, please.

I will. I remember, now, reading that about the Fuji.