Negotiate solution is a specific stage in the consultative sales process. You write your sales proposal so that you will not have to negotiate but you need to be ready to negotiate nonetheless. One of the reasons you may have to negotiate is on price. Despite your best efforts in assessing budget and communicating value, you still may get into a situation where your prospect is unable to go ahead with the proposed pricing.

The golden rule in pricing for professional services is to take care in deciding what rate to charge and then once you have set a rate you do not change it. You negotiate the shape of the solution but not the day rate of the people put forward. Here are some of the things you can change about the proposed solution without having to negotiate your rates:
Change the timing of payments

Sometimes the price objection is about the cash flow rather than the cost. If you can have some payment options available then this can help to win the go-ahead for the deal.
Change the timing of deliverables

Sometimes a project may contain elements which are not needed until later. This opens up the possibility of ‘phasing’ the project so that you can get the project started within the client’s existing budget and allowing them to pay for the next phase when they have additional funding.
Change the project scope

The project may contain non-essential elements that can be removed without impacting essential elements of the solution. For example, rather than do a full-scale implementation you may suggest starting off with a pilot implementation.
Use an alternative resource

Whilst you do not want to negotiate the rate of the people proposed, you could offer to use less skilled resource who may take longer to get the same amount of work done. Alternatively, it could be possible put forward more skilled people would get things done quicker.
Use client resource

Instead of proposing to supply an alternative resource, you could suggest that the client provides their own internal resources to do part of the project.