RE: How to pre-populate a field when new record is created?
Hi partner,
Is it possible to have it so that the 'price list' field is automatically populated with our main price list when someone creates a new opportunity without the user having to select it manually?
Yes, we can implement it using a business rule. The following are the specific steps.
1) Go to Advanced Settings > Customizations > Customize the system.

2) Expand Entities > Opportunity, click Business Rules, click New.

3) Set the condition to Status contains data. Add a action - Set Default Value, then select Field to Price List, select Value to the main price list.

4) In the top right corner, select the form scope. Save and activate the business rule.

The effect of this business rule is that whenever you create a new opportunity record on the selected forms, the field price list will be automatically populated with the value. When you manually change the value of the field price list or for an opportunity record that has already been created, this business rule will not work.
Users can then also create a quote from within the opportunity so is it possible to auto populate the price list on the quote from the opportunity?
D365 has already implemented it by default.
When you create a quote from the opportunity, the fields of new quote maps the fields of opportunity, which means that the price list of the quote is automatically populated by the price list of the opportunity.