void mapDisplay(map<int, Inventory> *mapn)
{
    //Following your example...
    map<int, Inventory>::const_iterator mapIter;
    mapIter = mapn->begin();

    cout << "Inventory map contents as follows: " << "\n";
    for (unsigned int i = 0; i < mapn->size(); i++)
    {
        cout << "At key " << mapIter->first << ": " << "\n";
        cout << &mapn[mapIter->first].toString() << "\n";
        mapIter++;
    }
    //Throws error C2039: 'toString': is not a member of 'std::map<int,Inventory,std::less<_Kty>,std::allocator<std::pair<const _Kty,_Ty>>>
    //Trying some alternatives, but if you could leave feedback as to why this does not work I would find it helpful. I've scratched my head for a couple hours now on it.
}