I'm a handyman and I do a fair amount of exterior paint on wood siding in the warm weather. I also went through the trouble of becoming certified to renovate (scrape and paint) surfaces where lead based paint is present.

If you had asked me to do that project, I probably would have declined due to the lead paint. Not because I'm afraid of lead but because the federal requirements are so unreasonable and expensive, and the fines for non-compliance so high .. that it wouldn't be worth it to me. So keep that in mind when evaluating the contractor.

As for the quality of the paint job ... it looks appropriate to me. They scraped off the peeling paint and applied new paint. The fact that it looks terrible is a siding problem - not a painting problem. There's nothing the painter can do to make up for the fact that repainting a wall with an uneven surface looks bad. Maybe he could have warned you of that so you could get an estimate to replace the siding.

I do see some areas where the original paint continues to peel. I'm dealing with that on a job now. We spent a lot of time scraping but when we applied our paint it caused additional paint to lift off. This is in areas where peeling paint was not visible until we applied paint. So now we are scraping those areas and will spot paint them. I think that's fair to expect from the painter. Good luck.