and it must be cash or certified funds.
You should not collect EMD just for application (to show seriousness).
Collect an application fee is enough to show seriousness.
Normally, EMD is collected if the move-in date is far from leasing signing/contract date. Say, 2 weeks or over.
If the tenant is going to move-in in 3-5 days after lease signing, you should collect 1st month rent+ deposit directly at signing time, no need for EMD.
In essence, EMD is a protection for taking the property off the market while waiting for tenant to move in.