How we change what others think, feel, believe and do
Keep showing interest, then backing off (then repeating the cycle) until they offer the deal you want. You can even back off after you have agreed a price, apparently getting 'cold feet' about the purchase.
Start by saying that you are at an early stage in your buying process, still finding out what is available and the sort of prices you can get. They continue to show interest. This should give them hope of 'stealing' the sale before competing sales people can make their pitch. Listen and then say the product seems great but you really should check out other sources first. Then say that to buy now, you would need to be made a really good offer.
This should get them to give you a good price. They may also seek to take advantage of your apparent ignorance, while of course your research has told you what a good price really is. This lets you check their tendency to deceive and also gives the opportunity to shame them into agreeing to a low, but reasonable, offer.
We've only just started looking ... This is rather nice ... Well, I guess I should really check out other places first ... How much could you do this for now? ... That's too much for me. I'll give you twenty. ... That's good ... Actually, I'd better not, I'll get into trouble ... Wow, that's a really great deal ...
I'm not in a hurry. It's early days yet. ... Go on tell me more ... Really? That's nice ... You'll have to offer a great price to tempt me today. ... I'm not sure, maybe I should check out other prices. ... That's better ... I don't know, though ... .
When you say that it is early in your buying, the sales person knows that selling to you will be difficult. But then when you show increasing interest, their hopes of a sale are increased again, only to be dashed when you say you want to look elsewhere, and then increased when you talk prices. This puts the salesperson on a rollercoaster of hope, wearing them down and making them increasingly desperate.
The longer you engage the sales person, the more time and emotion they will have invested into the process and the more they will want to achieve the sale to give some return on this investment.
The rollercoaster effect increases when you yourself seem to be rollercoastering too, swinging between desire and uncertainty. As the salesperson bonds with you, they will empathetically be tied to your apparent mood swings.
You can use nibbling as a part of this approach, asking for more extras to be thrown into the deal for no extra cost. These may even be offered without prompting, especially when the sales person has reached the lowest price they are allowed to offer.