Does closing waive a buyer's right to complain about something they should have caught earlier?

Not automatically, but it can, and whether it does depends heavily on what the agreement says, particularly its sandbagging position and its survival clauses. Closing itself — the act of completing the transaction — generally isn't treated as an automatic waiver of every right the buyer might otherwise have, because purchase agreements typically state expressly that representations and warranties survive closing for a defined period, and that indemnity obligations continue afterward specifically so closing doesn't wipe out the buyer's recourse.

Where closing can affect a buyer's rights is around something the buyer specifically knew about before closing and chose to close anyway, which circles back to how the agreement's sandbagging language (if any) is drafted — an anti-sandbagging clause can bar a claim on a known issue precisely because the buyer closed with that knowledge. Separately, some rights genuinely are meant to end at closing by design, such as the right to walk away over an unsatisfied closing condition, since proceeding to close is itself generally treated as accepting that the conditions were satisfied or waived.

Understanding exactly which rights survive closing and which don't, for your specific agreement, is worth confirming with a Treadstone business lawyer before you sign off on completing the deal.