Interior vs. Exterior Drains

Topic: 
Drainage
Question: 

I'm trying to get a question answered about waterproofing. My problem is water coming in along one wall and water damage along another wall that has rotted out the part of the stair case. All the waterproofing experts I've had in say I need this internal French drain sort of system whereby you drill holes in the block and run this new system into a sump pump. They say an exterior fix is only good for a few years at best and is enormously expensive. What do you think of these internal systems? Are they the best way to go? I really appreciate any answer you can give. We've been given quotes from $5,000 to $10,000 so before sinking that kind of money in, what advice can you give?

Answer: 

I for one find that working with the drainage on the outside of the home works best. It may not