Is there a big difference in mileage on an engine and on the car's body?

I'm looking to buy a used car from a friend of mine for $1200. It's a 1998 Honda Civic with a manual transmission, 1.6i engine but the car's body has a total of 273K miles and the engine has 65K. What's the big difference? Is the car worth buying and how long will it last me?

There are no magic ways to know how long an "old" car may last, a year or a month, or even a week. That car is 16 years old, the engine has been changed but how many miles are on that engine, was it rebuilt or just swapped out with another old engine? Many parts will wear out due to age, but exactly when will always be a mystery.