Wisconsin real estate contracts must be:

The requirement that real estate contracts must be in writing to be enforceable is a fundamental concept in real estate practice that directly impacts daily transactions and protects both buyers and sellers. This question tests knowledge of the Statute of Frauds, which addresses contracts that must be in writing to be legally enforceable. In Wisconsin, as in most states, real estate contracts fall under this statute due to their significant value and complexity. The reasoning process begins by recognizing that real estate transactions involve substantial financial commitments and property rights that require formal documentation. While verbal agreements might exist, they are generally unenforceable in court when it comes to real estate. Options C and D represent additional requirements that aren't necessary for basic enforceability, though they might be prudent practices. Option A is incorrect because verbal contracts for real estate violate the Statute of Frauds. This question's challenge lies in understanding the distinction between what creates a valid contract versus what merely adds layers of protection or formality.