We can start small as trust builds we can do large amount this will ensure both parties interests.
A scammer will first trade (for example) $50, $100, $200 or even $1000 first few days. They will build a good relation with your. One day you will send large amount of money for example $10k. You will not hear any response from them. I think having a mentality of building trust for both parties are very risky for trading.
I will always, suggest to use escrow service when you are trading crypto currency online. There will be some fees but it's worth for the safety.