I started to do this myself and am going to end up having to hire someone due to time constraints - I am trying to beat a rate lock for a re-finance and this is part of the appraisers comments before it can be underwritten
The entire porch (concrete) actually needs redoing and if I had time I would do it myself. I did rent a washer for the concrete but as I sprayed it loosened up a lot of paint that scraping alone didn't get, leading to even more work. Combined with the ceiling, a wicked case of food poisoning over the weekend and a time crunch and I'm s.o.l.
I have used PeelAway and wasn't overly impressed with the can I got. To be fair - it was the green product they make and at least some of the paint I was trying to remove was milk paint. I'll see if I can find the architectural variety and try that elsewhere. I have heard great things about it from a lot of sources - I just think circumstances were odd. I also grabbed a bottle of SoyGel but haven't tried it yet. I'll probably end up saving it for interior work. The guy at the salvage place raved about it so who knows.
As far as what doesn't work on the ceiling:
sanding - manual or a disc on a drill (Gator product - haven't dried some of their others)
spyder scrapers (works great on flat surfaces that aren't above my head)
manual scraping (owww)
Thanks for the feedback. Depending on what the painter says I may end up doing a crap job to meet the appraisers list and redo it properly over the summer.
The house isn't in a historic overlay and the neighborhood isn't too snooty so the vinyl wouldn't be an issue at the moment but I'd much rather keep wood if possible.