Should I buy this '88 190d?

[>mpg]

I'm new to the diesel world and so was the current owner of the 1988 190d with 131,000 miles. The current owner bought the car in hopes of having a good commuter car. It was purchased by him as a project car because the prior owner hit a deer and got rid of it.

The car starts and runs but he is having problems with extreme power loss. The car just refuses to get up to speed. He admits that he has no knowledge of diesels and hasn't taken it to a garage.

I took a picture under the hood and I'm curious as to what the first things I should try replacing if I purchase the car for $350. The body is rust free and the interior is nice.