Bricks, Masonry, Asphalt and Concrete - how about exterior block water sealing

I read the response to the split level home. I've got 4" high concrete block exterior, with exposed (non stucco) finish. The mortar joints are recessed, maybe called raked? With last years hurricane, we had quite a bit of interior flooding; I find out that many cells were filling with rain water due to simple wind driven impact with the wall. One contractor suggested elastomeric coatings. I have since read about Texcote and other, professionally applied coatings. Do these thick film coatings work? And, are there any that can be applied by a homeowner with the typical 5gallon bucket type airless sprayers? I've got some auto painting experience, and just don't see why a homeowner can't do this job.