Most of the time you see leak-proof window flashing details, they are for new construction. The step-by-step slideshow "Flashing a Flanged Window" and the article and slideshow "Flashing and Trimming a Window" are classic examples that cover the gamut of today's state-of-the-art flashing materials.
Replacement windows are a different animal altogether. Integrating tape flashing with the weather barrier (if there is one), is no small trick when the building is already sided. But that's no reason not to try. The result of leaks can be a legal mess, and it's always better not to involve your insurance company (see "Legal Adviser: Liability Insurance").
Leak-proof replacement windows in wood-frame walls rely either on a good quality sealants strategically placed (see "Installing Replacement Windows") or peel-and-stick flashing tape (see "Flashing Replacement Windows").
In a brick veneer home, peel-and-stick flashing is a critical ingredient. Getting it in the right place, however, is the tricky part (see "Replacing Windows in Brick-Veneer Homes").
Stucco is just a bear. The ferocious part is patching in stucco so it's not painfully obvious afterwards. It is possible to avoid an unsightly stucco patch around the window (see "Replacing Windows in Stucco Walls"), but getting it right will still be difficult. If you really want the patch to disappear, plan to stucco the whole wall, corner-to-corner, and no one will be able to tell the difference when you're done.
