Buy 560 SEC: Pro and Contra

I got an offer today that I don’t know at the moment whether to accept. It’s a 560 SEC with almost full equipment. From the sliding roof over black leather, airbag seat heating and on-board computer (like AMG) he has pretty much everything (unfortunately without a climate, but I don’t care either). From the outside he’s grey; he looks really noble. But the problem with the whole thing is that the engine doesn’t run. Probably the ECU is through because he has a chip tuning. the other one is not in question, since the seller says that the engine had already run rough before, jumped badly from time to time and needed the last time around the 30 liters. At the last start attempt nothing happened anymore: no clacking of the starter, no other noise, just nothing! Since then he stands around. However, that now already about 2 years. The letter has expired. What now speaks for the car is the good equipment and the favorable price. But, is the Pr He wants to have between 1,800 and 2,000 € for the coupe. Is the price okay? You should definitely remember that the engine may be defective. In this case, you get used engines or how expensive are these? I am already looking forward to many answers and tips. Because my wish to have a 560 SEC has been very great for years. And I would like to finally fulfill this wish. Answers can also be sent to my email as an alternative. Thank you very much in advance Markus