How do I refurbish my phone to sell?

I've rebuilt phones for my children and grandchildren's use and there are really only two parts to be concerned with, assuming the phone is fully functional and we're talking cosmetic rather than functional fixes.

The screen, obviously. It's glass and hardened so it takes a lot to leave scratches and visible imperfections but it can happen, and of course if it's cracked or broken in any way then replacing it is a must if you want top dollar for the phone. The good news here is that on these older LCD phones the screen prices are hitting rock bottom; you can easily find a new replacement for around $20 USD.

As for the rest of the phone, it's all pretty much one piece. If the rear camera lens covers are cracked they can be replaced individually, but for anything else such as dented sides, cracked rear glass or other cosmetic issues with the housing, then replacing the housing is about the only option. It's a major operation and requires gutting the entire phone and moving everything inside to another housing, but realistically it's the only way to refurbish the rear and sides of the phone.

The only other item I'd suggest is to check the charging port; if it's a good fit and working fine then leave it alone, but for a sloppy or intermittent fit or obvious damage you'll need to replace the lightning port flex cable assembly. With a new port the charging cable will fit well and give a good connection every time.

Other than that, make sure to wipe the phone and note in your listing whether it's iCloud locked and if it has a SIM lock and if so, to which carrier it's locked to. If it's your phone, remove it from your iCloud account and turn off FMI to ensure it's usable by your buyer.

Hopefully that'll give you some ideas and help you profit from the sale of your phone.

Ah, I did think of one other thing - it helps a lot to include the phone's IMEI number in your listing. That allows buyers to check for themselves to confirm there's no iCloud or carrier lock on the phone. If you're uncomfortable publishing that number for some reason, you can get an IMEI report online and include the report in your listing with the IMEI number redacted. That will give the buyer a fair amount of assurance the phone can be activated on their account.