Yes, because Best Buy is not a carrier. Verizon is the carrier so if Verizon is telling you that a 400 deposit will be required that same 400 dollar deposit will be required at Best Buy as well. Verizon sets their own rules for their services. Best Buy is just a authorized retailer of Verizon but is still bound to operate their sales in accordance to Verizon's rules and regulations.
Verizon or any carrier pulls a credit report and bases their judgement off that and looks at payment history with current carrier. No matter where you go for Verizon service there will be a deposit required if Verizon is requiring one.Have you tried AT&T?