These days, a lender may do a 120 day rate hold/preapproval...no cost to the customer.

I am a Realtor in the London/St. Thomas area of Western Ontario. If you are considering a new home, investment property, or commercial bldg, contact an independent Mortgage Lender ie: Dominion Lending, OMAC, Mortgage Intelligence & lock in your rate. Most will offer you 90 days. If you prefer a bank, shop an Independent broker & take that rate back to your bank. Believe me, you do not get the best rate first time from your banker. Most people feel the bank is trustworthy, well take my advice & shop. You will save thousands..