Would I use it a service such as you've described? No.Thanks AREA!
That's why I want to build something that return the ownership of service history back to the car owners.
We upload the receipts/ services we paid for and ensure it's as accurate as possible, while still having the benefit of digital record (easy to share & preserve etc)
Would you use it?
I have a dozen cars with likelihood of more to come. With insurance, tax, service, MOT, AA cover, etc. there's always some activity on the horizon, getting on for around fifty 'admin events' a year. I therefore use a spreadsheet as a year planner with a printed copy on the wall of my study to show at a glance what's coming along (May is very expensive). I use Omnifocus to provide reminders two weeks in advance. I also use these two tools to cover house insurance, health insurance, pet insurance, horse insurances = all those commitments that you don't want to accidentally forget about. Importantly, the wife can easily see these as well should something happen to me; insurance cover is pretty high up the list of things my wife needs to make sure continue if I'm six foot under. The reminder function of what I think you're suggesting has no benefit to me.
Insurance documents are also saved to shared Dropbox folders so family members can pull them up whenever required.
In terms of saving service records? Again, no. I scan in the paperwork, OCR and file it to DevonThink. I can find anything I want simply and quickly. For instance, if I want to see every service that had operation AP00.20-P-0054EW signed off as performed (actually, this has been more important that you could imagine) it's a simple query.
I understand why you feel there is a need, and there is. But there are tools that are happily doing it, and more, already.