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.

{
public:
    std::string name;
    std::string purpose;
    CAddressBookData()
    {
        purpose = "unknown";
    }
    typedef std::map<std::string, std::string> StringMap;
    StringMap destdata;
};
struct CRecipient
{
    CScript scriptPubKey;
    CAmount nAmount;
    bool fSubtractFeeFromAmount;
};
typedef std::map<std::string, std::string> mapValue_t;
static inline void ReadOrderPos(int64_t& nOrderPos, mapValue_t& mapValue)
{
    if (!mapValue.count("n"))
    {
        nOrderPos = -1; 
        return;
    }
    nOrderPos = atoi64(mapValue["n"].c_str());
}
static inline void WriteOrderPos(const int64_t& nOrderPos, mapValue_t& mapValue)