The offer process

Wanting to put an offer in on a PPOR. Going to say subject to finance and building inspection. Finance and inspection should not be an issue. What if we give a verbal offer subject to these conditions and then go cold for some reason ie personal, job security concerns etc? Can they ask/inforce for the reasons why, ie see the banking or building reports?

When is an offer an offer? If it verbal can we retract the offer at any stage? Is the offer only concrete when the contract of sale is signed by both parties?

The offer is only concrete once both parties have exchanged contracts. Whatever offer you verbally give to them now is not legally binding (neither would any written offer unless you explicitly say so.)

I'd recommend leaving the "subject to blah" clauses for your lawyer/conveyancer to put into the contract before exchange; for now just give them a number over the phone.