What should I know before talking to an estimator about facade takeoffs & shop drawings?

Hey everyone, i am part of a New Jersey - based team that supports teams with facade shop drawings and materials takeoffs. I handle marketing and sales.

I'm not an estimator myself and I'm definitely not here to pitch anything but I'd really appreciate some honest insight from those of you in the field.

What are the key things you'd want someone like me to understand before even starting a conversation with an estimator?

1. What frustrates you most when people try to "sell" you drawing services?

2. What do you look for when considering outside help(if ever)?

3. Any major red flags/ green flags?

I'd would love to just listen and learn from you folks who do this work directly. Appreciate all efforts and insights.