Septimia that was what I was tempted to do. But knew she wouldn't do it. And I've priced the job at our local sewing repair shop and he said £20. There's a back story on this - we have a young Romanian woman who cleans for us and does a good job. But she's so naive otherwise and seems to think we can solve all her problems for her. knows nothing about sewing - doesn't even recognise a sewing machine So we're trying to get her to stand on her own feet rather than solve her problems for her. She has now decided she's going to make the best of it - close the zip up to the missing teeth and use the poppers instead.
If you decide to help her with it, why not get her to unpick the old zip? That's the most tedious part of the job anyway and the skill - your skill - is in sewing the new one in.
I bought an outdoor fleece jacket with a windproof lining a few years ago for £30. Well worth every penny working out in the garden and fields etc. The zip died in November and I struggled on until I saw an advertisement in our local newsletter for a lady that did repairs and alterations. I bought the zip online for £5 and contacted the lady, I delivered the jacket and zip to her and 48 hours later it was ready for collection - she charged me £18 - well worth every penny.
Replacing zips in ANYTHING is my least favourite repair job to be honest. Personally, I wouldn't do the job, as it's for a friend there would be no expectation of recompense other than the cost of the zip. I would be inclined to show her how to do it and leave her to it.
Someone we know bought a cheap padded, fur-lined jacket online. About £25. Now a few teeth have broken off the zip. About 30", 75 cms. The zip is too lightweight for the jacket. I've replaced zips in jackets in the past and have a good long zip we could use to replace it. But the unpicking would be a nightmare. Should I show her how to replace the zip, or should I advise her to buy a new jacket?