PMI costs vary from one mortgage insurance firm to another, but premiums usually run about 0.50 percent of the loan amount for the first year of the loan. Most PMI premiums are a bit lower for subsequent years. The first year's mortgage insurance premium is usually paid in advance at the close of escrow, and there is usually a separate PMI approval process.

Lenders generally turn to a list of companies with whom they regularly work when lining up private mortgage insurance.

In most cases, PMI can be dropped after the loan to value ration drops below 80 percent. Find out from your lender what procedure to follow to have PMI removed when your equity reaches 20 percent.