Question

do the police need a search warrant if you willingly let them into your house or property?
yes; police officers need a search warrant no matter what when going to search a home.
yes; if you let them in without a search warrant anything they find cannot be used in court.
no; if you let them in voluntarily they are legally allowed to seize evidence.

Explanation:

Under the legal principle of consent searches, if an individual voluntarily allows police entry to their property, the police do not need a search warrant, and any evidence lawfully seized during that consensual visit is admissible in court. The other options misstate this rule: warrants are not always required, and evidence from consensual entry is usable.

Answer:

No; if you let them in voluntarily they are legally allowed to seize evidence.