The federal opportunity has four qualifications worth reading in full. It applies to target housing, defined in 24 CFR 35.86 as housing built before 1978, excluding housing for the elderly or people with disabilities unless a child under six lives or is expected to live there, and excluding any zero-bedroom dwelling. The 10 days is a default rather than a floor: the parties may agree in writing on a different period, longer or shorter. The buyer "may waive the opportunity to conduct the risk assessment or inspection by so indicating in writing" (24 CFR 35.90(b)). And the subpart does not reach every sale: 24 CFR 35.82 excludes sales of target housing at foreclosure. A buyer who believes federal law gives them an inspection period is half right in a way that will hurt them, because the half that is right covers lead paint in older housing and nothing else.
What sits behind it is unusually sharp for a residential rule. Under 24 CFR 35.96(c), "[a]ny person who knowingly violates the provisions of this subpart shall be jointly and severally liable to the purchaser or lessee in an amount equal to 3 times the amount of damages incurred by such individual", and 24 CFR 35.96(d) allows a court to award costs, reasonable attorney fees and expert witness fees to a prevailing plaintiff. Section 35.96(e) makes a failure to comply with the evaluation opportunity a violation of 42 U.S.C. 4852d(b)(5) and of section 409 of the Toxic Substances Control Act. EPA maintains a parallel rule at 40 CFR 745.110. None of that turns the lead evaluation into a general inspection right, but it does mean the one federal opportunity is not decorative.
The market runs two structures under one heading, and the difference is what a change of mind costs. In the first, the contract gives the buyer a period to inspect and then to object, ask for repairs or a price adjustment, or terminate, with the deposit governed by the contract's own terms. In the second, common in some states, the buyer pays a separate fee for an unrestricted right to terminate during a stated option or due diligence period; that fee is generally not returned, whether or not the buyer walks, and whether it is credited at closing depends on the form. The first buys a conditional exit; the second buys an unconditional one and pays for it separately. The forms and the vocabulary vary by state, so the question is which structure the contract in front of you uses.
The clause is about the deadline, not the report. An inspection produces a document; the contingency decides what a buyer can do with it and by when. A buyer who has the report in hand but has let the objection period run has a well-documented problem and no remedy. That is also why the two most common waivers behave differently: waiving the general inspection clause removes an exit and leaves the physical risk entirely with the buyer, while waiving the lead evaluation must be done in writing and is the only one federal law addresses at all.