Q: How many hours does it take to replace a 2006 BMW 750li transmission

It takes "roughly" 8 hours but if you have the Xdrive version, add 2 hours. The cost depends on exactly what you want. A new transmission? A used transmission? A rebuilt transmission? The recommended approach is to install a rebuilt that is obtained through BMW’s own rebuild channels. As far as the other cost element, the number of labor hours to perform a replacement, such is fixed by book values. Consequently, there is no such thing as a "good price" but rather, and this is critical, your attention should be focused solely on finding a person who is actually competent (not easy). Replacing a transmission (and "worse", rebuilding a transmission) is not like changing a tire. Even a small mistake is frankly disastrous because small mistakes can sometimes mean the ENTIRE job has to be done over again. If you are interested in a precise cost estimate, and ultimately transmission replacement, YourMechanic professionals in certain locales can assist with that. Please simply inquire based on your locale. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.