Thanks everyone on your thoughts. I ended up splitting the dates up as D.. suggested. However, I went the other way around, I bidded the off-peak period first (Apr 15 - Apr 18) and got accpeted for $46/night at Anaheim Marriott Suites. Then I tried to use the add more nights option, which as I had expected, got rejected saying no inventory is available at that price. I was going to place a bid for the peak period (Apr 13 - Apr 14), but suddenly a sale came up on Expedia for $116/night at Anaheim Marriott Suites (non-sale price was $169 as listed). So, I just ended up buying the 2 nights from Expedia (just to save the hassle of changing hotels). It works out to be ~$74/night for the 5 nights we stay in Disneyland.