For years now, if you needed a primer, there was only really one or two options, usually a Kilz product, and in oil or latex. Some stores carry there own version of these, but I have found most people tend go with the bigger name here.
These days, more and more people are taking on projects themselves, and doing the whole DIY thing. So it's best to really know what is out there, and what works best for different projects before you get started.
I tend to shop at Sherwin Williams for my paints, as it is close by, they are trained in paint, so they actually know what they are taking about (no offense to the box store guys), and in my opinion a better paint than the local hardware store stuff. Some companies have comparable paints...so this will at least help you get started. Check out some info here, on how to get discounts, and coupons on their paint.
All these paints below, can be found at any Sherwin Williams Store.
First we look at your WHITE primers..in Latex, and Oil-Based.
--A good basic LATEX primer that works well for a slight color change is the "Drywall Primer". This just helps your original color not peek through, or change the tone of your top coat....."Dry Wall Primer" $24
--A LATEX primer for covering up colors that are several shades darker than your new color.... "Multi-Purpose Latex" $33. This is a thinner paint, and may take 2-4 coats to cover a darker color. This paint is messy stuff, lots of splatter, so prep well.
--If you are doing a paint or plaster treatment over a wallpaper, you have to use an OIL-based primer, to lock in the paper, so it doesn't peel or bubble. This creates a very hard solid surface...."Pro Block Primer". $28. This is a contractor paint, so you wont find it on the shelf, they carry it in the back.
--For covering up over minor mold, water damage, or stains you will need a heavy ACRYLIC-ALKYD primer made for this, one that keeps it from bleeding back through....."Multi-Purpose Water-Based Acrylic-Alkyd Primer ". $33. This is a water-based acrylic-alkyd primer...this means, it cleans up with water, but acts as an oil for the hardness and durability.
--This primer is also good for prepping raw wood (it will need a light sand before the top coat).
--For covering up heavy mold, water damage, or stains, you will need to use and OIL-based primer, one that will lock it in, and be the best coverage so that doesn't show back through..."Multi-Purpose". $42
--For priming raw wood with heavy knots and tannin stains, a SHELLAC primer can be used just in certain spots, this primer is also good for covering orders and smoke damage......"White Pigmented Shellac Primer". $52 Because this is a shellac, it cannot be cleaned with water, and it's stinky.
This is the name of the product at this moment, this product is being changed to a water-based formula with no actual shellac in it....It will be called "White Synthetic Shellac" but it is not in stores yet.
There is also a spray can version of this paint, which is good for the smaller projects.
--For painting any kind of furniture, I always recommend using an OIL-based primer. Most furniture pieces are sealed with an oil-based sealer, or a wax, and occasionally, a latex-based sealer. An oil-based primer will ensure a good solid bond to any slick surface. If the furniture your painting is going to end up in a white or cream color, a white primer is good....For smaller pieces, a spray can will work "ProBlock". $4
For larger pieces, "ProBlock Primer" is best. $33
--For a zero VOC option in LATEX.... "Harmony Wall Primer" $44.
This paint has order eliminating technology, and helps improve indoor air quality, so it is a good paint for small areas with little ventilation . It also has anti-microbial properties to inhibit the growth of mold and mildew on the surface, perfect for bathroom walls. Also if your very sensitive to paint smells, this is the primer to use for most of the LATEX projects.
Next, the GRAY Primers in Latex and Oil-Based.
--For covering up walls that are dark, or rich in color, a gray colored primer works best. This hides the tone of the color underneath best. With a white primer you will need 2-4 coats of primer, to cover blacks, and reds. With the gray primer, you may only need one coat...."Mutli-Purpose Water-Based Acrylic-Aklyd Primer". This can be tinted in all the gray tones (see color chart below). This is the only primer that will tint to the darkest of the gray primers, the P6.
--When painting deep or rich color top-coat, having a gray tinted primer works well here . The color is more uniform, and true to the paint chip sample. The biggest bonus, less coats of your top color. A good basic primer for this is the...."Multi-Purpose Latex Primer".
--The same goes for painting furniture. When covering over a dark wood tone, or using a dark or deep top color, the gray OIL-based primer is perfect (see cabinet photos below). This stuff is awesome! Wish I would have had this years ago. The paint is very heavy bodied, and has great color coverage. It didn't make a splattery messy like the latex does either.
Here are the gray color choices P1-P6.
All of the primers can be tinted with these colors (with the exception of the P6)
The question then is....how do you know which color of primer to choose for your paint color?
Luckily, Sherwin Williams made a pretty fool proof system. On the fronts of some of the paint chips, there is a "P", which indicates it will need the tinted primer (not all of their paint chips types, have these on the front). On the back of the Sherwin Williams paint color chips, they have a P1-P6 number printed on them, if it is needed.
On the pictures below, the "P" is circled, as well as its primer color suggested on the back
I was surprised at the level of tinted primer that was needed for the colors. Like how a lime green color, needed a deep gray primer.
Let's say you have your favorite color picked out from some other brand, then what?
Take your paint color chip to Sherwin Williams, and find a color that looks close, use their guide listed, for the color of primer to use.
No number on the back? Then you can just use the plain old white, or none depending on the surface.
One of the last things I want to clarify for you, is about OIL vs LATEX Primer.
This only applies to primer....
You can use a latex, or oil based primer, and put LATEX paint on top. Just because you put oil primer down, doesn't mean latex paint wont adhere, quite the contrary.
If you are using an oil-based top coat, like for cabinets or furniture, I always say OIL is best for the primer.
I know oil is stinky! And messy!! Wear gloves, and a mask if you have to, and make sure you only clean up with the right products (paint thinner, mineral spirits, etc.). Or try the Mutli Purpose Acrylic-Alkyd for the durability, without the mess.
Here is a recent cabinet project I did, using the ProBlock Primer Oil-Base, in the color P5.
These cabinets were originally white...and not in great shape. A light wipe down with a cleaner, and a little bit of sanding on any chipped areas, got them prepped.
This was with just one coat of the primer (sorry for the grainy Ipad photo, but you can see how good it covered).
For the next coat I used a deep brown tone "Griffin 7026". I used Sherwin Williams, "Solo" latex paint here. I don't normally like to use latex on cabinets...but if you have to, this is the one to use .
It has good coverage, and is great on wood (overkill for use on walls). This is the contractors version of this paint, at around $40 a gallon.
The homeowners version of this is called "Pro Classic", which runs around $68 a gallon.
If you don't see the Solo out, just ask for it.
This is only 1 coat of the brown. If I would have used a white primer on these white cabinets, I would have needed at least 2 coats of this brown paint to cover.
Cabinets with the glaze.
I know there are alot of primers to choose from, and it can be overwhelming, so I hope this helps you in your future paint projects.