Only if the scope, incremental benefit and release mechanism justify the restriction for your business. Request an explanation of what the partner will do under exclusivity that it would not do under a narrower mandate.
Separate exclusivity over a named buyer from exclusivity over an entire modality, territory or future use. Preserve existing customers and products in a schedule. Define which contracts are protected if the representative introduces a prospect and the final agreement is signed later; a poorly bounded tail can outlast the mandate economically.
Build three scenarios: no exclusivity, narrowly scoped exclusivity with milestones, and the proposed broad grant. Use the same cost assumptions and identify differences in receipts, delays and lost alternatives. Do not assign a monetary opportunity cost without an explicit assumption and sensitivity range.
Possible negotiation asks include a paid minimum, a limited initial term, a list of eligible prospects, activity reporting and release when agreed milestones are missed. These are owner-side options, not representations of standard market terms. Counsel should review enforceability and any interaction with existing grants before execution.