When evaluating a savings tool, what are two examples of terms and conditions that may vary between depository institutions?

If a mortgage can be considered a savings tool, which I believe it can be relative to the equity built up in it, two terms are the interest rate the institution charges to borrow the money and also the allowable lump sum payments. There are both fixed term and variable rates. For the fixed term it is often for 5 years at a guaranteed interest rate, whereas a variable rate may have lower rates but it can fluctuate and so the fixed term is usually higher whereas the variable can be lower when it is purchased. As for lump sum payments, some institutions like credit unions will allow one to pay back a lump sum to the principal every year with a limit as to how much but this can also vary between institutions as do the interest rates.