Diagnostic equipment needed for 348 or 355 maintenance?

I am lucky to have an auto repair shop in the family and even though they work mostly on Infinity and Nissans, my cousin has always done a great job maintaining whatever I have driven. I also only pay for parts. I know it would be easy to maintain a 328 but I am wondering if special diagnostic equipment is needed to maintain 348s or 355s? I know that the computers he uses on the Jap cars dont seem to work well with my Saab. Does one need specialized equipment to work on these later cars?
In addition, my cousin has worked on a couple of 80s Ferraris. He rebuilt a TR tranny that someone had cracked going over something. He tells me that he loved the simplicity of the car, how easy the engine comes out, but was shocked by the thousands of dollars needed in parts.
If you are wondering why I just dont buy a 328..... the reason is that I barely fit in them and the AC system is not able to keep the car reasonably cool in the Florida heat. I love everything else about the 328.....in particular the reliability and low maintenance.

 

For the record....I never bought a Saab. The car was purchased by my wife before I met her. Its a weird car in my opinion. Thanks for the info, I will see if my cousin has the diagnostic equipment you mentioned.