diff --git a/contracts/Marketplace.sol b/contracts/Marketplace.sol
index 51b7aaf..b92230d 100644
--- a/contracts/Marketplace.sol
+++ b/contracts/Marketplace.sol
@@ -23,8 +23,7 @@ contract Marketplace is Collateral {
   {
     bytes32 id = keccak256(abi.encode(request));
     require(request.client == msg.sender, "Invalid client address");
-    require(request.size > 0, "Invalid size");
-    require(requests[id].size == 0, "Request already exists");
+    require(requests[id].client == address(0), "Request already exists");
     requests[id] = request;
     transferFrom(msg.sender, request.maxPrice);
     funds.received += request.maxPrice;
@@ -36,11 +35,9 @@ contract Marketplace is Collateral {
     bytes32 id = keccak256(abi.encode(offer));
     Request storage request = requests[offer.requestId];
     require(balanceOf(msg.sender) >= collateral, "Insufficient collateral");
-    require(request.size != 0, "Unknown request");
+    require(request.client != address(0), "Unknown request");
     require(offer.host == msg.sender, "Invalid host address");
-    require(offers[id].expiry == 0, "Offer already exists");
-    // solhint-disable-next-line not-rely-on-time
-    require(offer.expiry > block.timestamp, "Offer expired");
+    require(offers[id].host == address(0), "Offer already exists");
     require(offer.price <= request.maxPrice, "Price too high");
     offers[id] = offer;
     emit StorageOffered(id, offer);
diff --git a/test/Marketplace.test.js b/test/Marketplace.test.js
index 222d4ec..6326c7e 100644
--- a/test/Marketplace.test.js
+++ b/test/Marketplace.test.js
@@ -64,14 +64,6 @@ describe("Marketplace", function () {
       )
     })
 
-    it("rejects requests of size 0", async function () {
-      let invalid = { ...request, size: 0 }
-      await token.approve(marketplace.address, invalid.maxPrice)
-      await expect(marketplace.requestStorage(invalid)).to.be.revertedWith(
-        "Invalid size"
-      )
-    })
-
     it("rejects resubmission of request", async function () {
       await token.approve(marketplace.address, request.maxPrice * 2)
       await marketplace.requestStorage(request)
@@ -112,13 +104,6 @@ describe("Marketplace", function () {
       )
     })
 
-    it("rejects an expired offer", async function () {
-      let expired = { ...offer, expiry: now() - hours(1) }
-      await expect(marketplace.offerStorage(expired)).to.be.revertedWith(
-        "Offer expired"
-      )
-    })
-
     it("rejects an offer that exceeds the maximum price", async function () {
       let invalid = { ...offer, price: request.maxPrice + 1 }
       await expect(marketplace.offerStorage(invalid)).to.be.revertedWith(