Constitutional Carry On The Move! Vote is tomorrow...with an amendment for a permit.

[Interceptor_Knight]

If I were to buy 2 guns at the same time there apparently is a different background check form for multiple gun purchases within 5 days that only require 1 background check and 1 fee for more than 1 gun, instead of running a separate check for each gun at $13 for each check.

There is only 1 WI Handgun purchase form and 1 version of the Federal 4473. There is no different background check or additional fee for 1 or 1000 handguns purchased at once. If you purchase 1 or more handguns at once, it is considered a single purchase and a single DOJ check and $13 fee. If you purchase more the next day, it is a DOJ check and $13 fee for each "purchase", not each handgun. You may purchase long guns and handguns together and it is still a single phone call to the WI DOJ and a single $13 fee.
If you purchase 2 or more handguns within 5 consecutive business days, the FFL is required to submit a form which records the multiple purchase. http://www.atf.gov/forms/download/atf-f-3310-4.pdf You are not required to do anything and there is no charge to you for the FFL filling out this form.
You may purchase an infinite amount of long guns or receivers at once or within 5 business days, etc and there is no special form to be filled out.