You willl want to lock after you have a home & loan amount in contract.

I my opinion, in today's environment, you should lock for 45 days as deals are taking longer to close. If you need to extend your lock in the future for a few days or a week or so you may do this. The cost is .003 per day. Example: $100,000 loan and the lock needs to be extended for 7 days, it will cost you $30 per day for the lock extention i.e 7 x $30 = $210 additional for the lock.

It makes no sense to lock without a home and contract. It will cost you money and homes are getting multiple bids and the acceptance procedure currently is very protracted. Find house, bid, win bid, get in contract, lock loan. She was right lock after contract.

I sell homes and do home loans and if I can be of assistance to any Trulia members, give me a call or email. We are in a very competitive market.

You should lock your rate when you go under contract. Your lender will give you the best advice on rates for the week. I would not pay in advance for anything until the appraisal is ordered and the home is under contract and the inspections completed.