When a pass of CreateTransaction fails to select enough bitcoin to meet the nFeeNeeded the next pass through may select a far smaller collection of inputs.  Currently it will continue to use the old fee amount based on the larger set of inputs, which can cause a non-trivial over-payment.

This may be the cause of the behavior reported here: https://www.reddit.com/r/Bitcoin/comments/5ltw5n/bitcoin_core_v0131_sends_enormously_high_fee/

Long ago fixing this was tricky due to a catch-22 between signing the transaction and knowing how much fee was required.  But after #9465 the whole algorithm will run using a dummy signature, so when there is already a change output fixing up the fee after finding a sufficient transaction should be a matter of a ~2 line change.

void SetBroadcastTransactions(bool broadcast) { fBroadcastTransactions = broadcast; }
    
    bool AbandonTransaction(const uint256& hashTx);
    
    static std::string GetWalletHelpString(bool showDebug);
    
    static CWallet* CreateWalletFromFile(const std::string walletFile);
    static bool InitLoadWallet();
    /**
     * Wallet post-init setup
     * Gives the wallet a chance to register repetitive tasks and complete post-init tasks
     */
    void postInitProcess(boost::thread_group& threadGroup);
    
    static bool ParameterInteraction();
    bool BackupWallet(const std::string& strDest);
    
    bool SetHDChain(const CHDChain& chain, bool memonly);
    const CHDChain& GetHDChain() { return hdChain; }
    
    bool IsHDEnabled();
    
    CPubKey GenerateNewHDMasterKey();
    
    
    bool SetHDMasterKey(const CPubKey& key);
};
class CReserveKey : public CReserveScript