Converting garage into temporary bedroom???

We live in 3BR house with attached garage, one bedroom is very small more like an office room. The small room is currently my daughters room, she still uses toddler bed so it works for now. She is 3 1/2 and wants a big bed now, there is no way we can put a twin bed in there we already have half her toys in the livingroom. We are considering giving her our room and using part of the garage for a temporary room until we can sell/move or build an additional room. We don't want to change any of the structure there is already a window and we don't need to do anything electrical there are plenty of electrical outlets. I was thinking of painting, some cheap carpet and maybe a temporary wall or maybe just hang a curtain for a divider. We will still be using part of it for a storage and washer/dryer are in garage.
Would we need any building permits for technicality purposes, we don't want to get in trouble for some stupid technicality.

What would be the best way to keep it cool in the summer, we have central air and could keep the door open or would a window unit work better? Also anybody know of a good way to keep the spiders out, we always have spiders/webs all over the garage, I always found it kind of strange because we rarely find either in the house.

In most places i the US you will not get in any trouble of you do what your proposing...... Just painting some walls and hanging up some curtains wont cause you any hassle. On the other hand there are some neighborhoods that have covenants and rules that border on the absurd....... Combine this with nosy neighbors and you may have some zoning/building inspector out to bother you. If your not changing the structure in any way just go ahead and do it. Make a temporary wall thats movable and not connected to the existing walls or ceiling........ If your local building inspector knocks on your door you DO NOT HAVE to let him in. Tell him to make an appointment..... Them move the stuff around so it looks like its just storage for when he returns.... Dont mention to your neighbors what you are doing to any room in your house,,,, As much as you think they might be your pal I wouldnt bet on it. Nosy neighbors with a crappy existence are always a hassle.

That would be one solution. Depending on your location, there may be concerns regarding heating and all. You shouldn't need a permit for internal, cosmetic work that you are describing.

I honestly do not know but I am just saying here..
Do you have an air conditioner or heater in there for the weather? Are you aware of the bugs that get into garages?
Just some things to think about.
I know you probably dont care im JUST SAYING.
Best of luck though.
I hope it turns out.

before putting side walls up, put some insulation batts against the walls, and put the temp wall over them. this will solve your weather concerns. have the room sprayed for spiders, this will remove them.
if the garage already has walls, then just have them painted the colour of choice and have the room sprayed.
buy a large shower curtain rod that its the right size to go around all your "garage and laundry" things, divide with a bright happy coloured shower curtain or curtain.

you could use cheap carpet squares and lovely foot rugs for the floor.

add cute curtains for the window.

finding a cute little pink fan will cool her if it gets hot in there even through you're leaving the door open.

if you have a garage roller door, spray it all over with surface bug spray - spiders looove all the hidey holes in them. and then cover wtih a long lovely curtain. your daughter doesn't want to look at roller doors when she's trying to feel at home.

buy some pieces of thin wood or some canvas, and paint with your daughter. let her paint anything she likes while you do two canvases/woods of the same pattern. you might paint two with stripes of different shades of pink. and she might paint a pink unicorn for eg. then hang them up in her room as a featured section. it will look amazing and she'll be very proud of herself when she sees it.