What would you like to do in Manila?
I went to Manila last year, and as person who loves visiting museums and cultural places, there's not that much to see in my opinion. I only stayed 2 days, and I felt that was enough.
I highly suggest using Grab, as taxis are known for not using the meter and overcharging.
I can't provide much in terms of motels, but I did stay at an Airbnb condo which was fine.