Never sleeping on FB marketplace again...

I rarely check for lego on my local FB marketplace but I was bored last weekend and saw that someone in my city was selling Assembly Square (still assembled, all parts & minifigs, rather dirty but that's fine) for $200. I offered $175 expecting a negotiation, but he just wanted it out and I drove over right away. Is my plan for cleaning them crazy? I've been carefully taking it apart, and plan on soaking them in a giant storage tub of dawn soap & water, then sifting and cleaning/rinsing them...