I would suggest you better do your R&D before opting for any kind of tour packages. There are a lot of fraudulent websites and agents online that will leave no chance to dupe you. Better go through multiple travel websites and tips. If possible, talk with someone whom you know who has already made the trip. The person would be best to advice you. Also, while getting the tickets or booking any hotel etc., have a look at the coupon websites beforehand like Groupon, Kiindly or Ebates to avail some good deals and offers. Singapore is a beautiful city indeed and the Disney Land situated there is one of the best. I wish you a memorable journey there!