This question was for presenters this week, but open to all to respond.
Did/Does including options to donate or other features that involve monetary transactions add any complexity to website projects? What resource or development time considerations should one keep in mind?
It can be a simple add, especially with an existing tool like Paypal or Stripe. For WordPress there is a very richly featured plug in called GiveWP that allows you to create a donor wall, send follow up emails, etc. It does require some time to get familiar with the tools and configure it, but makes it pretty doable for a beginner or intermediate web manager.
If you are using third-party systems like Raisers Edge, it can add development time and complexity because the developer will have to figure out how to get data entered from a website form into the database. It’s possible to embed a form from a third-party software company, but in my experience, those are not very friendly to mobile phone website visitors. So, if possible I would allocate the time and budget for a developer to set it up for you to make it mobile-friendly and easy to use.