We are migrating everything off our core server shortly but we need outside expert help. We know what we want to do but we are nervous about the execution so we want to hire a reputable consultancy.

I want to contact a few consultancies to get quotes to do the implementation. But even this is unfamiliar territory. I am thinking of asking the consultancies for estimates for implementation times, costs, rollback plans, return to operation times and willingness to execute some the project remotely. I think there may be three to four days work spread over three to four weeks. Would this qualify as an sla? What information should we be asking for? What should we be looking out for in the replies and what should we be insisting on?