Most importantly....what are you using the blender for and how often?
Ingredients like ice or nuts and using it multiple times a day will definitely decrease it's lifespan.
In this case you would need a professional/commercial model.
My 20 year old Oster blender is superb.
After using it, I do unscrew the base and remove the gasket and blade for cleaning, towel dry, and re-assemble it just barely hand tight for storage.
Before using the blender again, I make sure the gasket is seated properly and tighten up the base. I have had no problems or leaks.
If the lid leaks, it is probably over filled, however a liquid splattering the lid too much can be corrected by laying some plastic wrap over the top of the blender and then the lid will fit more snug.