It is difficult from this question to determine what level of discussion has taken place here, so I will work to some assumptions. It seems that you have had contact with a number of recruiters, and any attempts to negotiate have not been very successful.
The key element of a successful negotiation is that both parties have a desire to negotiate. If you are connecting with ad-hoc recruiters on a need-to-use only basis, then they’ll typically see this as spot business and are less likely to want to negotiate with you – why should they if there is no exclusivity, repeat opportunity or relationship? If you’re willing to address these points, a recruiter will have more of an incentive to be open to negotiating on price.
If there is no movement on price (a likely scenario with the cost of candidate attraction rising annually), don’t forget that the rebate period is another negotiable detail – one that recruiters are more likely to move on. By taking advantage of a generous rebate period, the risk is suddenly removed. If you pay 20-30% for a great candidate that works out, you’ll feel that this is a worthwhile investment. If the candidate leaves but you have negotiated a longer rebate period, then you’re avoiding a painful experience. If the recruiter carries the same risk that you do, the quality of your candidates will also improve significantly.
There are recruiters out there that have set themselves up to support smaller businesses, and will create commercial arrangements to reflect the startup or a smaller element of your business. By taking the time to find the right recruiters, you’ll not only save time but money too.