Itay - do you use a CRM package such as Salesforce. Is for have Marketo send the contact info and score to SF. Within SF or similar package you can then set triggers to your sales stages. This lets each automation package do what it is designed for - marketo drives the lead, salesforce manages the opportunity and sales process. Within Marketo you can have triggers that change the sales status though this should be driven by point scores. An approach is to map out each activity type: direct mail, events, webinars, trade shows and go through the logic steps for each. You can then determine at what point does a member (name) turn into a suspect (have performed a defined activity) and finally into a prospect (a cetain level of activity and also type and level thereof - fills out short and progressive long forms, attends an event and shows real interest, etc).