diff --git a/flex_marketplace/src/marketplace/royalty_fee_manager.cairo b/flex_marketplace/src/marketplace/royalty_fee_manager.cairo
index ee53ab9..a385317 100644
--- a/flex_marketplace/src/marketplace/royalty_fee_manager.cairo
+++ b/flex_marketplace/src/marketplace/royalty_fee_manager.cairo
@@ -1,28 +1,41 @@
 use starknet::ContractAddress;
-
+use starknet::class_hash::ClassHash;
+use flex::marketplace::royalty_fee_registry::{
+    IRoyaltyFeeRegistryDispatcher, IRoyaltyFeeRegistryDispatcherTrait
+};
 #[starknet::interface]
 trait IRoyaltyFeeManager<TState> {
-    fn initializer(
-        ref self: TState,
-        fee_registry: ContractAddress,
-        owner: ContractAddress,
-        proxy_admin: ContractAddress
-    );
-    fn transfer_ownership(ref self: TState, new_owner: ContractAddress);
-    fn owner(ref self: TState) -> ContractAddress;
+    fn initializer(ref self: TState, fee_registry: ContractAddress, owner: ContractAddress,);
     fn INTERFACE_ID_ERC2981(self: @TState) -> felt252;
-    fn get_royalty_fee_registry(self: @TState) -> ContractAddress;
+    fn get_royalty_fee_registry(self: @TState) -> IRoyaltyFeeRegistryDispatcher;
     fn calculate_royalty_fee_and_get_recipient(
         self: @TState, collection: ContractAddress, token_id: u256, amount: u128
     ) -> (ContractAddress, u128);
+    fn upgrade(ref self: TState, impl_hash: ClassHash);
+}
+
+
+#[starknet::interface]
+trait IERC2981<TContractState> {
+    fn royaltyInfo(
+        ref self: TContractState, tokenId: u256, salePrice: u128
+    ) -> (ContractAddress, u128);
 }
 
 #[starknet::contract]
 mod RoyaltyFeeManager {
-    use starknet::{ContractAddress, contract_address_const};
-
+    use openzeppelin::upgrades::upgradeable::UpgradeableComponent::InternalTrait;
     use openzeppelin::access::ownable::OwnableComponent;
+    use openzeppelin::upgrades::UpgradeableComponent;
+    use openzeppelin::introspection::interface::{ISRC5Dispatcher, ISRC5DispatcherTrait};
+    use starknet::get_caller_address;
+    use starknet::{ContractAddress, contract_address_const};
+    use super::ClassHash;
+    use super::IERC2981Dispatcher;
+    use super::IERC2981DispatcherTrait;
+    use super::{IRoyaltyFeeRegistryDispatcher, IRoyaltyFeeRegistryDispatcherTrait};
     component!(path: OwnableComponent, storage: ownable, event: OwnableEvent);
+    component!(path: UpgradeableComponent, storage: upgradable, event: UpgradeableEvent);
 
     #[abi(embed_v0)]
     impl OwnableImpl = OwnableComponent::OwnableImpl<ContractState>;
@@ -32,50 +45,66 @@ mod RoyaltyFeeManager {
     #[storage]
     struct Storage {
         INTERFACE_ID_ERC2981: felt252,
-        royalty_fee_registry: ContractAddress,
+        royalty_fee_registry: IRoyaltyFeeRegistryDispatcher,
+        #[substorage(v0)]
+        ownable: OwnableComponent::Storage,
         #[substorage(v0)]
-        ownable: OwnableComponent::Storage
+        upgradable: UpgradeableComponent::Storage,
     }
 
     #[event]
     #[derive(Drop, starknet::Event)]
     enum Event {
+        #[flat]
         OwnableEvent: OwnableComponent::Event,
+        #[flat]
+        UpgradeableEvent: UpgradeableComponent::Event,
     }
 
     #[external(v0)]
     impl RoyaltyFeeManagerImpl of super::IRoyaltyFeeManager<ContractState> {
         fn initializer(
-            ref self: ContractState,
-            fee_registry: ContractAddress,
-            owner: ContractAddress,
-            proxy_admin: ContractAddress
-        ) { // TODO
-        }
-
-        fn transfer_ownership(ref self: ContractState, new_owner: ContractAddress) { // TODO
-        }
-
-        fn owner(ref self: ContractState) -> ContractAddress {
-            // TODO
-            contract_address_const::<0>()
+            ref self: ContractState, fee_registry: ContractAddress, owner: ContractAddress,
+        ) {
+            self.INTERFACE_ID_ERC2981.write(0x2a55205a);
+            self
+                .royalty_fee_registry
+                .write(IRoyaltyFeeRegistryDispatcher { contract_address: fee_registry });
+            self.ownable.initializer(owner);
         }
 
         fn INTERFACE_ID_ERC2981(self: @ContractState) -> felt252 {
-            // TODO
-            0
+            return self.INTERFACE_ID_ERC2981.read();
         }
 
-        fn get_royalty_fee_registry(self: @ContractState) -> ContractAddress {
-            // TODO
-            contract_address_const::<0>()
+        fn get_royalty_fee_registry(self: @ContractState) -> IRoyaltyFeeRegistryDispatcher {
+            return self.royalty_fee_registry.read();
         }
 
         fn calculate_royalty_fee_and_get_recipient(
             self: @ContractState, collection: ContractAddress, token_id: u256, amount: u128
         ) -> (ContractAddress, u128) {
-            // TODO
-            (contract_address_const::<0>(), 0)
+            let feeRegistry = self.get_royalty_fee_registry();
+            let (receiver, royaltyAmount) = feeRegistry.get_royalty_fee_info(collection, amount);
+            if (!receiver.is_zero()) {
+                return (receiver, royaltyAmount);
+            }
+            let interfaceIDERC2981 = self.INTERFACE_ID_ERC2981();
+            let supportsERC2981: bool = ISRC5Dispatcher { contract_address: collection }
+                .supports_interface(interfaceIDERC2981);
+            if (supportsERC2981) {
+                let (receiverERC2981, royaltyAmountERC2981) = IERC2981Dispatcher {
+                    contract_address: collection
+                }
+                    .royaltyInfo(token_id, amount);
+                return (receiverERC2981, royaltyAmountERC2981);
+            }
+            return (receiver, royaltyAmount);
+        }
+
+        fn upgrade(ref self: ContractState, impl_hash: ClassHash) {
+            self.ownable.assert_only_owner();
+            self.upgradable._upgrade(impl_hash);
         }
     }
 }
diff --git a/flex_marketplace/src/marketplace/royalty_fee_registry.cairo b/flex_marketplace/src/marketplace/royalty_fee_registry.cairo
index 038ead0..b382099 100644
--- a/flex_marketplace/src/marketplace/royalty_fee_registry.cairo
+++ b/flex_marketplace/src/marketplace/royalty_fee_registry.cairo
@@ -16,7 +16,9 @@ trait IRoyaltyFeeRegistry<TState> {
     fn transfer_ownership(ref self: TState, new_owner: ContractAddress);
     fn owner(ref self: TState) -> ContractAddress;
     fn get_royalty_fee_limit(self: @TState) -> u128;
-    fn get_royalty_fee_info(self: @TState) -> (ContractAddress, u128);
+    fn get_royalty_fee_info(
+        self: @TState, collection: ContractAddress, amount: u128
+    ) -> (ContractAddress, u128);
     fn get_royalty_fee_info_collection(
         self: @TState, collection: ContractAddress
     ) -> (ContractAddress, ContractAddress, u128);
@@ -107,7 +109,9 @@ mod RoyaltyFeeRegistry {
             0
         }
 
-        fn get_royalty_fee_info(self: @ContractState) -> (ContractAddress, u128) {
+        fn get_royalty_fee_info(
+            self: @ContractState, collection: ContractAddress, amount: u128
+        ) -> (ContractAddress, u128) {
             // TODO
             (contract_address_const::<0>(), 0)
         }