help a newcomer who has some questions

you need to play around with it and find out what works for you. what kind of lights are you using?

Figure out the Cubic Feet of the room (Need height data) and get an exhaust fan that will suck all the air out in 3-5 minutes. Get a Carbon Filter that matches your exhaust fan.

You will need to duct the exhaust out of the tent.

how many plants are you growing in this area... if you are only growing like 1-2 plants.. a simple air freshener or gel will fix the smell problem... also.. when it comes to heat issues, what type of lights are you using... a CFL grow, a small fan will be more then enough... i dont have any experience with hps and mh lights, so i cant comment on how to deal with that heat

Really need more info,

Access to room, or area - door? - access on 6' wall or 4' wall.
Access and being able to reach and work on everything you start.
If this an insulated space? is it an area, within an unconditioned space? are any of the walls exterior?

For heat & ventilation this will depend on the load, which is dependent upon your environment and location (winters real cold or summers real hot)

@ kevin i was thinking about using cfl lights
@ BendBrewer the hight of the area is 4.5ft and the depth of the area is 2 ft

@iNUPE i will be growing 1-2 plants

@ WattSaver access to the room is directly off my hallway so anyone who comes to the flat could gain access to the room, the area has no external walls its all internal, there is no air conditioning if that makes any sense and it is not insulated. the winters seem to be getting colder by the year and the reverse is true for the summer