Annual operating expenses and management fees. No management fees. Limited transaction costs. No ongoing marketing expenses. Return fluctuates, depending on the securities held by the fund.
Return is relatively fixed, although it varies somewhat as bonds are called, redeemed, or sold.
At least annually, and monthly on some funds. At least quarterly. Shares can be redeemed at any time. Units can be redeemed at any time. Mutual funds generally have no set term.