Turbos of this vintage are good only if the service history is available showing frequent oil changes otherwise an abused turbo could be on its way out depending on mileage. The Turbos either have 15 inch straight spoke (Dracos) wheels or 16 inch fan blades (Hydras). These were options and does not indicate a difference in Turbo models. However, the type of wheels may indicate a certain vintage of vehicle, as some years came std with hydras or dracos.

Generally there was a turbo (B230FT - 160HP) or non turbo(B230F - 114hp) engine in these 700 series cars. Some cars however were fitted with a Turbo + kit that boosted the HP to 188 and this was an option but std if you owned a 780T. Off topic but may be of interest, there was also a 16v dual overhead cam engine (B234F - 155HP) that came fitted on the 740GLE.

The designation 740 is the whole series of wagons and sedans. The 744 generally meant 4 door aka sedan and the 745 = 5 doors and wagon. Thats all.

The 900 series is a similar car to the 700 series and was developed on the same platform that eventually eclipsed the 700 series. Both models are fairly similar as many parts are interchangeable between the 7 and 9 series cars. However, the 9's usually had fancier options and better equipped with electrical gizmos etc. Oh and the edges look a little softer/ rounded on the 9 series. Those are the major differences.

Hope this helps,

Tim