Hi brains trusts, long term stalker first time poster. I would love some advice on getting this wall ready for painting.
By way of background these walls are brick rendered and paint had been flaking in small locations exposing the white filler. Instead of sanding the wall I made a call to scrape the paint off. I did this as I was concerned that the paint would continue to flake and would have to strip it back at a later time. I'm thinking original painting was likely done by an enthusiastic amateur (much like myself) without adequate prep as paint has also been flaking in many areas over the internal render where there is no filler.
My thoughts are that I will need to scrape back all the white filler (using a dust mask) and make a huge mess. Then, assuming the filler was used to cover an uneven surface, apply a skim coat, sand then seal the skim coat and then paint.
Before I commit to hours of vacuuming I wanted to check this was the right approach or if there's other recommendations? Bonus points for tips on how to remove the filler as quickly and cleanly as possible.
Close up of paint, filler and the rendered wall.. 
The wall in question. To the right is a wall without filler that paint has been scraped from.
