New drywall all the way. Especially if you want new trim.

Verbo, you’re an angel for answering! Could I ask you to explain why? (I don’t doubt you at ALL, I’m just dumb!!! And sorry also, with sheetrock how do y’all get around electrical outlets, etc? THANK YOU AGAIN

Is the knockdown just on the ceiling or is it on the walls too? $47 sounds insane and if this is a competitive bid in your area I can only imagine the cost covering with new rock. Covering over with new sheet rock would also involve removing all trim, building out all window and door frames to match the new sheet rock thickness and adding electrical box extensions throughout. Maybe pulling down cabinets, dealing with HVAC ducts, etc, and once it's done It will never be the same and and believe it could come close to $100K.

Skim coating would be my option and something I've done in the past so I don't get the $47K price tag, maybe other bids for the same job is needed.

I hate knockdown and think it was used to avoid a third (finish) coat of drywall mud using lower skilled workers. (same with popcorn ceilings). I skim coated my kitchen remodel over new sheet rock and it's a cut above in quality over just painting new sheet rock. The ceiling is flawless without the tiny dimples seen from the texture of the sheet rock paper. No light shadows from waves caused by a ceiling joist being a 1/8" lower than the others and is perfection to the limits.

It took me time and I'm not a professional but perfection requires skill not every taper/finisher has. Quality of the work should be your top priority here and if you hate looking at the knockdown imagine looking at a horrible skim coat you just paid 50K for.

Another question; why does the contractor need to remove the knockdown? In most cases it's just skimmed over.

Just skim coat it. I don't think they will be removing the knockdown ceiling texture after it has been painted, maybe even multiple times. It should cost maybe 1/9 of the cost given you.

I appreciate all of you so much.