DIY Attic insulation removal, seal, and replace? Worth it?

Two quotes so far, $4k to remove existing attic insulation. Not sure if that includes sealing, vent baffles etc. Another quote was I think $5200 for removal and then replacement but dont think it was blow in cellulose.

So....how DIY is this? Removal seems to be the hardest part. Rent the machine which is a drive to get. What do you do with the giant bags of old insulation now? If it's landfill, that's like $500 I'm guessing not including time and gas.

Pumping in new insulation where I'm located, bay area norcal, means doing this from 8am to 11am before attic gets hot now. Not ideal.

Don't like the idea of spending that much to hire someone SINCE I need to do a crawlspace clean out and likely plastic wrap all underneath.