If you will have some free time to spare i would love some input on it, before i go and blow up all the components 
Hi, @mancera1979
Good questions.
No, as it will be relying on the UNO 5V regulator, and it will not be able to handle the pump motor current and shut down 5V supply.
No, for the same reason.
No for the above reason.
The Ultrasonic will be okay on the UNO 5V as well as the IR sensors.
Do you have a DMM?
Tom... 
What exactly is the DMM? Also, the current draw should fall within range of 5V pin when I calculated it, the stepper takes 200mA approximately and the pump is 150-220mA as well. Or is there some other limit? Read somewhere it's about 800mA
Hi,
Digital MultiMeter.
Can you please tell us your electronics, programming, arduino, hardware experience?
Thanks.. Tom...
Programming pretty solid in various languages, electronics is a tad worse this is a school project and we kind of overshooted our capabilities here, so i am trying to catch up some knowledge here. And i do not have DMM, no. I have done one project with arduino before including basic game with LCD screen buttons LEDs etc.. but i generally like tinkering with this stuff 
Alright after a LOT of googling i found my answer i suppose. I'll copy my response from other forum here, this is what i found:
After a ton of googling i found more sources claiming the same thing, so i guess that's what I'll go with. Maximum current that can be drawn from 5V pin depends on the input power method. For USB it's 500mA minus what the board is using (about 50mA). For the VIN pin, the current depends on the input voltage. The higher the voltage the lower current can be drawn from the pin. This is due to the on-board regulator that has poor/no heatsink. In ideal conditions, the supplied voltage to VIN is about 6.2V, so the regulator only needs to drop 1.2V and that is the lowest it can go. At this point the current draw is max 800-900mA, minus 50 that the board is using and some safety margin, lets say 750mA. However, i need the power supply to be higher voltage than 6.2, since i need to power the motors and drivers, and those drop the input voltage by about 1.5V as well, since i got inefficient ones of course.. the motors still need about 6V, so the input voltage should be around 7.5V. And that's what i will provide. It seems like the ideal solution for my project, it's exactly 5xAA battery, it's perfect for motors even with the driver drop, the regulator will have to drop about 2.5V to get it to 5V, so not that much heat will be created and therefore it will operate normally longer before shutting down, and will allow me to safely draw about 600mA from the 5V pin, thanks to the lower voltage drop required. And when i summed all the component currents, it's about 550mA, so perfectly within range. Also worth noting I won't run this for very long at a time, maximum is like 15-20 minutes before a break so the regulator will have plenty time to cool down. Only other limit there is is the 40mA per IO pin (summed up to max 200mA for all pins), and that won't be a problem because only things powered from IO pins are 2 LEDs and a buzzer, and those doesn't consume over 20mA individually, so i think i found the ideal perfect solution. Thanks for all the input and whoever read it all this far, congrats!
What do you think about this all? I feel it's pretty solid, found multiple sources saying approximately the same thing and it actually looks believable.
Hi, @chameleonn
Don't forget the battery output will not be constant, it will drop especially when the 800 - 900mA draw is occurring.
You will need to do some experiments with your arrangement to make sure the battery voltage does not drop low enough to cause the 5V regulator to lower its output and cause a controller reset.
Before getting serious about code,
Assemble and check each peripheral on its own, and code to make sure you can communicate with or control each one.
So my advice;
Get a DMM, $20 budget DMM is fine.
Get the hardware and experiment, your project will cause, as you have said, many different and changing load currents.
Tom...
PS. Have fun......
Please note that all AA batteries are not created equal.
Old-fashion carbon-zinc are rated 1.55V
Alkaline batteries, 1.5V
Rechargeable batteries, 1.2V
So I would not rely that much on the 4/5/6 batteries count.
Oh yeah i know that! I've double checked the voltages on the labels, and it is alkaline one 1.5V, that is also the most common on in here. You can basically either get a cheaper one or more expensive one, the latter being rechargable. There's not much in between, and even the print on those is 1.5V so i hope it's right.