Clear primer.
You didn't mention whether you were using latex or oil based primer and paint, but generally the point of using primer is so that you can paint over it with any form of wall paint. Just read the label on your primer can to make sure it is compatible. On the other hand, if you wanted to paint the primer over the satin gloss, you need to sand the surface lightly to remove the sheen of the paint and provide a suitable surface for the primer to adhere properly.
Yes, after ensuring that the surface is clean, oil-free and dull. Lightly sand the shiny surface to help the new paint adhere. Even though the paint is marketed as paint with primer, it still requires basic prep work prior to application.
Not directly. You will need to use a primer made to adhere to oil and will accept a latex topcoat.
No
It will work over another latex paint, however it won't be as scrubable as a normal top coat, and it won't adhere as well as a paint over a primer. Better to apply the primer, then the paint. If the surface is clean and deglossed though, you really don't need a primer and can coat the surface with a quality wall paint.
Either oil or latex primer can be used over interior latex paint.
yes. However, you cannot use an oil base paint over a latex primer. If you change your mind on the paint, you must strip the paint before you use an oil based paint on the primer.
Primer is a base coat that can accept all types of paint so no stripping is necessary and you can definitely primer over primer but remember to fill and sand before to eliminate blemishes and maintain a smooth finish.
You'll need to paint over it. Use a good primer-Kilz is a good one. Follow the instructions for applying the primer. Then apply a new coat of paint.
The paint finish doesn't significantly change the surface preparation necessary. If the paint is the same type (water based going over waterbased or enamel over enamel) then the preparation is simply: * cleaning, * remove loose material, * fill any holes or hollows, * sanding and * wiping, If you are changing the type of paint (eg: painting waterbased over enamel) you may need to use an etch primer to "key" the surface and give the new paint a texture to grip onto after sanding, and otherwise prepare as above.
yes, it works perfectly, although I used a semi gloss. The paint is tougher and is less likely to soften due to moisture in the bathroom.