Business strategy requires a view at the horizon and longer term thinking. A business review should occur every 3 years with minor course corrections no more than once per year.
As you might expect, there is no good answer to this question. Companies have sold in as little as 45 days, but this is rare and uncommon. An audit of your company's financials, systems and organization can offer guidance. A well prepared company will bring higher and more qualified offers.
Salesforce management is a problem every business has. What is your expected wallet share per customer, per engagement or per market region. Every business should have an effective, managed CRM strategy with active sales management overseeing day to day activities.
All engagements are tailored to your business requirements. With exception to board participation, engagements can be as short as 120 days.
Taking market share is hard. You are effectively eating another's lunch. Review opportunities to improve your margin, finding customers, products and markets which add to your incremental profitability.