While working on this PR https://github.com/bitcoin/bitcoin/pull/18570 I ran into a bit confusing situation where in one function a **CWallet reference** was expected while two others dealt with **CWallet pointers**. My initial reaction was: `let's harmonize them by making them references`. However, not being part of the PR itself I did't change anything and completed the PR first.

Now, after having analyzed the `rpcwallet.cpp` code I came to the conclusion that:

* converting them all into references is not the solution as they're originally **shared_ptr**s
* but also: there is no (visible) reason why every RPC function should begin like this:

```cpp
std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
const CWallet* const pwallet = wallet.get();
```

This clearly defeats the purpose of shared pointers for no obvious reason. *Maybe I am missing something?*

In my (unpublished) [code changes](https://github.com/brakmic/bitcoin/commit/0b3ee615491edf6f542631bf6ae6f72eac406550) all raw pointers got replaced with **shared_ptr**s but kept their original names (that is, *pwallet*). In the end, they're pointers too, so the most of the original code remained untouched.

However, some of the helper functions couldn't be changed because external code is accessing them and I didn't want to make this task "virulent". So I introduced new ("Ref") variants that expect **shared_ptr** parameters, namely: 

```cpp
void EnsureWalletRefIsUnlocked(const std::shared_ptr<CWallet>);
bool EnsureWalletRefIsAvailable(const std::shared_ptr<CWallet>, bool avoidException);
```

I have tested the code, with python and boost-tests, and could not find any errors. 
But before opening a PR I would like to open a discussion about this. 

Is there any reason to keep on working with raw pointers when every function call actually begins with *shared_ptr*s?

Regards,
}
            if (options.exists("lockUnspents")) {
                throw JSONRPCError(RPC_INVALID_PARAMETER, "Use lock_unspents");
            }
            if (options.exists("subtractFeeFromOutputs")) {
                throw JSONRPCError(RPC_INVALID_PARAMETER, "Use subtract_fee_from_outputs");
            }
            const bool psbt_opt_in = options.exists("psbt") && options["psbt"].get_bool();
            CAmount fee;
            int change_position;
            bool rbf = pwallet->m_signal_rbf;
            if (options.exists("replaceable")) {
                rbf = options["replaceable"].get_bool();
            }
            CMutableTransaction rawTx = ConstructTransaction(options["inputs"], request.params[0], options["locktime"], rbf);
            CCoinControl coin_control;
            
            
            coin_control.m_add_inputs = rawTx.vin.size() == 0;
            FundTransaction(pwallet, rawTx, fee, change_position, options, coin_control,  false);
            bool add_to_wallet = true;
            if (options.exists("add_to_wallet")) {
                add_to_wallet = options["add_to_wallet"].get_bool();
            }
            
            PartiallySignedTransaction psbtx(rawTx);
            
            
            bool complete;
            pwallet->FillPSBT(psbtx, complete, SIGHASH_ALL, false, true);