It depends on your timeframe. If you have 2-3 years you can see potential substantial drops. Perhaps 20% or more depending on the housing type. I do not agree with your assessments that there has not already been some nice depreciation in these neighborhoods because there really has been. I can show you comps in each of the areas where recent sales are lower priced then similar floorplans in those same areas from the not so recent past. As someone who is very familiar with the I15 corridor I am quite certain of my statements.
I am not going to go into a rent verses buy number crunching exercise for you because in my opinion you cannot put a dollar value on home ownership.
I will say that I do believe that if you base the decision of renting verses buying ON NUMBERS ALONE, then in the long run waiting to buy is better. However there is a pretty vast differential in terms of opinions (on this board) about the price of home ownership.
Financially I have what I call a reserve and I have a downpayment fund for a home. My reserve is a sum of money I have in case of a calamity, job loss, or a sudden interruption of income. This reserve is not measured by a dollar amount but is measured temporally. That is, the reserve is used to pay bills and such for about 1 year in case I cannot generate income. My downpayment fund for a home is a totally seperate entity.
I realize that many people do not have such a savings structure. Raising kids is not cheap and basically it is really hard to save money these days.
Again, I do think there will be some potential big savings down the road. Perhaps 20%, perhaps more. Even if you can wait another year you may find a 5-10% savings.
This is just my opinion though and I know renting sucks because I rent and I would rather enjoy home ownership then renting. Still, I have to look at the numbers and for me I have not found anything that adds up.