I'm considering getting an fp4 as an upgrade for my s21. Although I was wondering if its worth the money or not. should I just wait for fp5 to go down in price. Should I not go for a fp entirely and instead seek some better value alternatives I am after all on a very tight budget.
I used to only get lower mid-range phones (~€250, and not latest models) and keep them as long as possible, mostly due to financial and environmental concerns. My last phone broke a few months ago so I got a Fairphone 4 as a replacement.
I'm very satisfied so far, but of course I'm not accustomed to fancy phones either so I'm aware that the bar is lower for me. Functionally speaking it does what I want it to, and feels good enough to fulfill my modest needs even in 4-5 years from now when requirements will have gone up.
The price is significantly higher than any other phone I'd bought - but I'm fine with that due to the extended warranty. I'll save money from not buying another phone in 3-4 years, and the added peace of mind from not having to replace the whole phone if anything were to break is worth some money in itself too.
But all the above would only convince me of 80-90% of the price. The fair production and environmental/personal freedom aspect of the phone are both the reason for the higher price but also why I'm happy to pay the price. I'd rather know that €500 is supporting things I want to see more of, than €300 is encouraging and perpetuating things that dislike.
But I also fully understand that I happen to have a little money to spare - a few years ago I was very tight with money, so as much as I would've liked to support it I'd have to make do with what I had. There's other ways to help if money's tight: Like I think also FP themselves say, "the most sustainable phone is the one you're already using" (or something along those lines).
In short, my advice from my personal (limited) experience would be:
__
Finally, one note on the warranties: iirc (do correct me if I'm wrong), the FP4 will allow for an extended warranty of 5 years only until the end of 2023, after that it'll be 3 years. So if you're going for a FP4 it'd make more sense to buy before the year ends. The FP5 continues to offer a 5 year extended warranty regardless of when you buy it.