How do you work with your constrictors

[Yuval Yizhaki]

Hey, 

when Im finding some interesting property some times its hard for me yo know what is the maximum price that i can offer, 

The solution for it is to send constructors to give an offer, and that with thir opinion and offers I can calculate the maximum offer. 

the problem is that Im not finding constructors that’s  willing to make an offer before Im getting in to the offer, and If they are, they want money for that. 

I will like there your opinion about it.