Unless you're ladened with cash most folks purchasing Real Estate will do so by obtaining a mortgage. There are things that everyone needs to know about the mortgage process and preparing yourself to obtain a mortgage.
These days people need to submit a preapproval/prequalification letter along with the Contract to Purchase (Offer in Massachusetts) BUT there are many more things to attend to. The folks at KCm have produced a fantastic infographic to aid people in this mortgage process.
What You Need to Know About Qualifying for a Mortgage