Repairing a seized engine could cost anywhere from $3,000 to $5,000 depending on the problem. This includes a lot of labor — to fix it, your mechanic will need to tear your engine apart, find the problem, replace anything broken and then put it back together.
If the concept of driving an engine that's recently been disassembled scares you, you always have the option to replace the engine entirely — for at least $5,000.
In some cases, the cost of repair or replacement can be so high that it makes more sense to simply sell the car outright.