@Rahul D.
Yes, I would recommend pulling a permit now. It will be much worse if you get caught doing the work without a permit.
Not sure what municipality you are in, but many towns, especially those where transfer stamps are required to sell, will look at the listing to see if recent work was done. Think of the pain you will have to go through if the town red tags your house after you have a seller and you are ready to close.
In addition, look at paragraph 23 (g) of the Multi-board real estate contract. I have had buyers attorneys ask for proof of permits. It happens often.
Many "contractors" do not want to go through the contractor registration process in Dupage county because it requires them to show proof of insurance (both liability and workmans comp if they have employees), not to mention the $100-$300 yearly fee.
@Kenneth Garrett is correct, just about everything requires a permit. Dupage county (unincorporated) takes it a bit further than some of the othe municipalities in the area, but that is just the cost of doing buisiness.
@Nino Alfano
What is an EZ permit??? never heard of that.