Location
If the hotel is easy reachable, close or within walking distance to public transportation and the places you want to visit then in most of the times it could be the best option. But think twice before you choose hotels on noisy main streets or rooms without air-conditioning if it is hot outside.
Rating
Well, it depends very much on the country you are planning to go. Do not expect a 3 star hotel to be the same quality in France and Egypt. Usually international hotel chains are more reliable, but you can also do some research on local hotel rating before you make up your mind.
Type
There are many different kinds of hotels and other accommodation properties. Think what kind of experience you are looking for? Large hotels are usually informal. In smaller hotels you can get more personal service. Guest houses are best for getting to know the locals. Bungalows or apartments will let you escape from everyone. And so on.
Services & Facilities
This you can usually find out quickly by reading hotel description or official website. Think what services you would like to use and if the desired hotel matches your needs. It is always nice to get some complimentary things or services.
Staff
Friendly hotel staff can make your stay more pleasant. Sometimes it can be even more important than comfort. Make a call or write an e-mail to the front desk to find out if they are friendly and helpful. If you are not so good with foreign languages, check what languages they speak.
Membership
Do you have any member card of an airline or credit card that can give you discounts or let you earn points for your stay? Maybe you are a member of some hotel group or chain? Do not forget to use these membership cards and get the benefits you deserve.
Online reservation
There are online hotel reservation sites that give special discounts or reward you for bookings, or let you negotiate the price. It's even better when you can compare online rates from many suppliers on one site. Use the advantage of online reservation services!