Well this instructable is for you. I'm going to show you how to stay in Beijing and see all the main sites in Beijing for less than $200 in US dollars.
Those sites are
-Temple of Heaven
To see these sites properly, you will need to be in Beijing for 3 nights. Depending on your arrival and departure times, this will give you 3 to 4 days in Beijing which will be plenty.
Step 1: Getting to Beijing and your Hotels
Getting to Beijing
This will be your biggest expense and one I can't help you with. Fear not. There are many ways to get cheap air fares from your home city to Beijing. Have a quick check online and you will find many useful sites with plenty of information on getting cheap airfares.
After airfare, hotels will be your next biggest expense so this is where you can save plenty of money. Dorms are the cheapest beds and also the best way to meet fellow travellers and have fun. The prices for dorm beds start at around $8 a night. You use http://www.hostelworld.com to find cheap reasonable hotels. The key is to choose a hotel in the center of the city. This will help cut your cost down a lot.
My personal favorite is the Central Youth Hostel (see pic).
Once you have booked your flight and know when you'll arrive, choose your hotel (remeber central location) and use an online service like Skype to call the hotel (call during China business hours) and book your beds. Caost of the call is $2 max.
Hotel budget for 3 nights - $24
Total so far - $26