Earnest Money Deposit

I am looking at 2 properties priced at $1,449,000 and $1,499,000 respectively, and I want to send in a letter of intent/offer to purchase. I also want to require seller's credits.

How will this turn out if opt to not offer any earnest money deposit? If I have to offer earnest money, will I get away with just $5K or will I need at least $15K, especially considering the increasing pivot into a buyer's market nowadays.