Your posts are great. Keep up the good work :)
I work in a startup and have been fielding a lot of recruiter calls. Like many other startups, recruitment costs are simply not something we can afford with our tight budget.
One tactic I found to stop getting constant calls and emails from the same recruiter is thru honesty and building awareness of our business position.
I let them know that we can't afford the costs now but we might be in a better position in a couple of years. By that time, I'd like to select a recruiter based on their professionalism, practices and ethics.