What are the sales strategies for commercial offers?

So you have made a commercial offer for the consultation of a construction project. The customer is convinced that you are technically very good at this project. And the customer holds other meetings and also receives offers from other companies. The next day, after you have sent your offer, call and speak with the customer and ask for the offer. Then you learn that you have a good deal, and the client says the price is reasonable, but he needs a bit more research and makes a decision in the board meeting.

After the phone call, you will not receive any updates or callbacks for your offer for a week. What would be the best strategy at this point to activate the process and complete the deal? If you call and ask about the situation and if you are still waiting for something, what can you say to convince the customer to work with you? What would be a tactic to speed up the decision making process? For example, can you use a scarcity method, as you estimate, that you have to get new projects in a short time and make an agreement as quickly as possible?