Well, it is the tropics after all, isn't it? Life of all kinds thrives in a hot, moist environment. I doubt anyone can be 100% effective at controlling pests in the tropics. The number one preventative measure in the home is to get rid of whatever is attracting the critters. This is easier said than done. Ants, flies, cockroaches and mosquitoes are attracted by things we can barely see but keeping the house free of food particles or open containers should be a priority. This web page contains other suggestions as well.
Natural Insect Pest Control
I hope your definition of "crawly" doesn't include lizards. They are your friends, unless they "pee" on your head.
Investing in a good mosquito net to hang over your bed is a good idea.
btw, the "ultrasound" insect repellents are worthless
Here is the ultimate mosquito solution:
Mosquito MagnetŪ | Home