diff --git a/Cargo.toml b/Cargo.toml
index 3c7d3db..742ac64 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,10 +13,10 @@ crate-type = ["cdylib", "rlib"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [dependencies]
-near-sdk = { version = "5.1.0", features = ["unstable"] }
+near-sdk = { version = "5.3.0", features = ["unstable"] }
 
 [dev-dependencies]
-near-sdk = { version = "5.1.0", features = ["unit-testing"] }
+near-sdk = { version = "5.3.0", features = ["unit-testing"] }
 near-workspaces = { version = "0.10.0", features = ["unstable"] }
 tokio = { version = "1.12.0", features = ["full"] }
 serde_json = "1"
diff --git a/src/deploy.rs b/src/deploy.rs
index d921ce0..413d179 100644
--- a/src/deploy.rs
+++ b/src/deploy.rs
@@ -31,7 +31,9 @@ impl Contract {
 
         let code = self.code.clone().unwrap();
         let contract_bytes = code.len() as u128;
-        let minimum_needed = NEAR_PER_STORAGE.saturating_mul(contract_bytes);
+        let contract_storage_cost = NEAR_PER_STORAGE.saturating_mul(contract_bytes);
+        // Require a little more since storage cost is not exact
+        let minimum_needed = contract_storage_cost.saturating_add(NearToken::from_millinear(100));
         assert!(
             attached >= minimum_needed,
             "Attach at least {minimum_needed} yⓃ"
@@ -74,13 +76,11 @@ impl Contract {
         #[callback_result] create_deploy_result: Result<(), PromiseError>,
     ) -> bool {
         if let Ok(_result) = create_deploy_result {
-            log!(format!("Correctly created and deployed to {account}"));
+            log!("Correctly created and deployed to {account}");
             return true;
         };
 
-        log!(format!(
-            "Error creating {account}, returning {attached}yⓃ to {user}"
-        ));
+        log!("Error creating {account}, returning {attached}yⓃ to {user}");
         Promise::new(user).transfer(attached);
         false
     }
diff --git a/src/lib.rs b/src/lib.rs
index a3cc42e..2e24752 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,9 +5,9 @@ use near_sdk::{near, Gas, NearToken};
 mod deploy;
 mod manager;
 
-const NEAR_PER_STORAGE: NearToken = NearToken::from_yoctonear(10u128.pow(18)); // 10e18yⓃ
+const NEAR_PER_STORAGE: NearToken = NearToken::from_yoctonear(10u128.pow(19)); // 10e19yⓃ
 const DEFAULT_CONTRACT: &[u8] = include_bytes!("./donation-contract/donation.wasm");
-const TGAS: Gas = Gas::from_tgas(1); // 10e12yⓃ
+const TGAS: Gas = Gas::from_tgas(1);
 const NO_DEPOSIT: NearToken = NearToken::from_near(0); // 0yⓃ
 
 // Define the contract structure
diff --git a/tests/sandbox.rs b/tests/sandbox.rs
index a6f89dd..69f8481 100644
--- a/tests/sandbox.rs
+++ b/tests/sandbox.rs
@@ -1,27 +1,26 @@
-use near_workspaces::types::{AccountId, KeyType, NearToken, SecretKey};
+use near_workspaces::types::{AccountId, NearToken};
 use serde_json::json;
 
+const TEN_NEAR: NearToken = NearToken::from_near(10);
+
 #[tokio::test]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let sandbox = near_workspaces::sandbox().await?;
-    let contract_wasm = near_workspaces::compile_project("./").await?;
-    let contract = sandbox.dev_deploy(&contract_wasm).await?;
+    let root = sandbox.root_account()?;
 
-    let alice = sandbox
-        .create_tla(
-            "alice.test.near".parse().unwrap(),
-            SecretKey::from_random(KeyType::ED25519),
-        )
-        .await?
-        .unwrap();
+    // Create accounts
+    let alice = create_subaccount(&root, "alice").await?;
+    let bob = create_subaccount(&root, "bob").await?;
 
-    let bob = sandbox.dev_create_account().await?;
+    let contract_wasm = near_workspaces::compile_project("./").await?;
+    let contract = sandbox.dev_deploy(&contract_wasm).await?;
 
-    let res = contract
-        .call("create_factory_subaccount_and_deploy")
+    // Launch new donation contract through factory
+    let res = alice
+        .call(contract.id(), "create_factory_subaccount_and_deploy")
         .args_json(json!({"name": "donation_for_alice", "beneficiary": alice.id()}))
         .max_gas()
-        .deposit(NearToken::from_near(5))
+        .deposit(NearToken::from_millinear(1700))
         .transact()
         .await?;
 
@@ -48,5 +47,30 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     assert!(res.is_success());
 
+    // Try to create new donation contract with insufficient deposit
+    let res = alice
+        .call(contract.id(), "create_factory_subaccount_and_deploy")
+        .args_json(json!({"name": "donation_for_alice_2", "beneficiary": alice.id()}))
+        .max_gas()
+        .deposit(NearToken::from_millinear(1500))
+        .transact()
+        .await?;
+
+    assert!(res.is_failure());
+
     Ok(())
 }
+
+async fn create_subaccount(
+    root: &near_workspaces::Account,
+    name: &str,
+) -> Result<near_workspaces::Account, Box<dyn std::error::Error>> {
+    let subaccount = root
+        .create_subaccount(name)
+        .initial_balance(TEN_NEAR)
+        .transact()
+        .await?
+        .unwrap();
+
+    Ok(subaccount)
+}
\ No newline at end of file