Multivitamins ,more often than not,are composed of inorganic minerals,which are very poorly absorbed by the body and most of them are toxic to the body,causing free radicals and various health problems,including the kidney.
1 If you want b12 , take deactivated yeast
2 For vitamin d just go expose your skin to the sun about 30minutes to an hour.
3 Omega 3 need to be very filtered if you use if from the ocean,but there are plenty of natural sources.
4 Vit a synthetic(palmitate) form is a known cancer causing substance in some forms. Research them if you really want it,but carrots give easily 100%
5 If you want to eat well I suggest using this website http://nutritiondata.self.com/tools/nutrient-search , which is using official USDA as a source for information,but adds %, contrary to original source.
6 Some of the most nutritious and bioavailable are sunflower seeds http://nutritiondata.self.com/facts/nut-and-seed-products/3076/2
Pumpkin seeds,peanuts and Sesame seeds for calcium(theres also savory herb and kale,etc), buy bulk and organic or at least no pesticide etc, if you're serious you can buy a corn grinder to dehull them,but it's cheap hulled also .
6.1 But don't forget to bake them in a ceramic cookware to 350 degres Celcius to remove possible small quantities of bacterias.
7- Easiest way to take is to blend sunflower and pumpkin and add liquid honey and mix with the spoon to make clumps (moderate taste/you can add melted chocolate/or chips) You can add maple syrup aswell.
8- Best way to make it is to buy organic apples, peel them, then cut all except the core(you'll get it fast with practice), and then blend that to make a paste.
Then mesure for example 3/4 cup sunflower 2/4 pumpkin seeds 1/4 peanuts or whatever the dosage you want, theres also a nutrient calculation tool on the website, you'll get almost 100% of everything (including considering the estimate of nutrient loss/plant content variation,methods of cultivation,and body absorption)
There you go,don't fall for the easy multivitamin scam, it's not hard to get all the nutrition if you go the scientific route. Theres also whfoods.com but their numbers are off sometimes. Don't hesitate if you have questions,but please make your own research to spare my time as I have helped you alot alredy.