I've got permission to search the yard of an old house from the 1870's or 80's. The house is vacant and has been for 40 years, and the owner just cut the grass (weeds)and won't do it again til next year. I have tomorrow to search and the next chance will be in a couple weeks. But 1st I have to find a knife that he lost. How would you go about doing a quick search of the grounds? It has about a 1/4 acre yard.