Where is the best place to get money orders in the USA with no fees?
Also do all banks allow you to deposit a money orders without having any issues?
Banks, supermarkets, drugstores, maybe some gas stations sell money orders. The fee will tend to be lower at Walmart and grocery stores than at banks. However, having certain higher end bank accounts allows you to get them with no fee. For example, Wells Fargo Prime Checking or Premier Checking.
I have banked with a few banks. Some banks' mobile deposit terms did not allow money orders to be deposited that way and some allowed them. Sometimes an ATM can't read the amount automatically and asks me to enter it. For in person deposits, I have never had an issue, other than an occasional extended hold on the funds availability if it's a large deposit. As part of the application process for a new bank account, I have seen banks ask about my plans to deposit money orders, but I don't know what they do with my response or what they do if my subsequent banking activity differs from that response.
