Painting

      Most of the walls in your home are likely to be latex paint.  Latex paint is a poor surface to hang wallpaper on.  The ideal surface to install most wallcoverings on is an oil-based enamel undercoat in the same color as the background color of wallpaper.  The undercoat (primer) should then be sized with an acrylic wall prep.

     Oil-based undercoats need a few days to 'cure' because they dry so slowly.  Once dry, they are a hard surface that is watertight.  You will be able to strip wallcoverings off of oil-primed walls without undue hardship or damage.  You can't say that for latex paint.

     If you have plaster walls and they are not in good condition, you should paint them with pigmented shellac.  Shellac is alcohol-based.  It prevents water stains and 'hot spots' from bleeding through.  Unfortunately, it is also harder to work with.  It dries very fast.  Be sure to get disposable paintbrushes and roller covers.  Good ones will cost you more in alcohol solvent to wash than they are worth.
     
     In some cases a quality pre-mixed wall prep will prevent you from having to prime your walls with oil or shellac.  An acrylic prep used over a top-quality acrylic wall paint will do a passable job.  But remember, sealing and priming your walls is the only way to assure you won't have damage from stripping in the future.