Part of what you pay for tree removal is insurance: -In case they drop a branch or the whole trunk on your house, garage, shed...or neighbor's property -In case someone gets hurt on your property in an inherently risky job The "free" job could end up costing you. I really do wonder if that oak tree might yield a good value in boards. But, if the tree is dead, are there rotten spots or insect damage that negates the usefulness?