Do I absolutely need this kind of setup? Do I need the big fancy fan, heaters and humidifiers?
You will definitely need all that stuff if you don't already have it. Heater's, humidifiers, dehumidifiers and A/c are optional but may be needed to actually grow pot depending on your climate and conditions in the garage you plan to set it up in.
To many 'ifs' here to go into detail without more info but a basic setup like you're looking at is probably a lot cheaper than trying to put together a grow piecemeal. I have a small Vivosun tent and it seems just fine but it's the only tent I've owned so don't have a lot to compare it too.
Many times in the past I've recommended a new grower start with something like this. If it turns out they are no good at growing then not so big an investment to lose and they could at least get half what they paid selling it off. If it turns out they are great at it and want to go bigger it'll make a great veg tent.
I have a hard time keeping temps down in the 4x2' tent in the warmer months but my main grow room is a converted cold storage room in the 'basement' which is a 10x30ft concrete bunker under the house where I have to heat it sometimes even in summer as it never got over 64F in the 21 years I've owned the place. The room temp can be 80F for months but the floor and two outside walls are around 60F as the ground freezes down to 8' in the winter and is all clay that holds the cold really well. I grew in a well insulated garage that had a house sized gas furnace in it but I built a 5x12' grow room inside so I didn't have to heat the whole garage. 6" walls with R40 insulation for the room. I vented into the attic only to have it raining inside when spring came around. Climbed up to have a look and it was a winter wonderland up there so if it gets cold where you are, don't do that.
Here in the spring I just have to worry about overland flooding. Only once did the basement get water in it but almost a foot so wasn't just a bit wet.
Loads-o-fun!
