What is a high mileage for a BMW 745 or 750

BMW pro here, geographic location will determine alot, a well maintained BMW will exceed 300,000 miles. I've personally seen beyond that. 100,000 pertains to "back in the 60's", before they had the technology of today..todays standards 200,000 is equal to that of their 100,000....absolutely love either model....are you thinking of purchasing? if so CARFAX CARFAX CARFAX....and what year is it, message me with more info

Personally the N62 engine is having trouble with engine oil consumption lately due to bad valve stem seals. I have had many engines start smoking and burning 1 qt of oil in 500 miles. I would advise to stay way from that engine for the time until BMW sorts out the issue they are having. Now the 750 depends if you talking about the new or old ones. The N73 v12 engine is an expensive engine to own with all the carbon issues from the direct injection system and also fuel injector problems made the car very expensive to own. From late 05 though the 750 was no longer a v12 and started to use the N62 that I mentioned above. Personally the engines are great and will with proper care last over 300,000 no problem but do your research on the car you want first. And always have a specialist look it over before purchasing it. Hope this helps.