We bought some sofas secondhand when moving into our first home. They were great, and they held up well for many years. But ultimately we sold them and bought new ones because we didn't know if they had the fire-retardant chemicals that used to be mandated in CA (until they were discovered to be carcinogenic). The new sofa (from Costco) seems good but the sofa chairs (from Wayfair) are not so good.

It seems like the frame in the back has some sort of support that is made out of a material that is closer to cardboard than wood. When our kids run into it, the back of the chair deforms a bit and has to be bent back. I have no idea why the frame of a chair would be made out of something so weak. I expect we'll have to replace them in 5 years or so, and we'll aim for something more old-school.