how much cash should i have before thinking about buying a home?

Every purchase would be different. Before you would even think about buying a home go to a lender and get pre-qualified for the highest amount possible. The lender will let you know by the type of loan you are getting what percent of the purchase you will need to put down. After you are comfortable with the amount of your purchase based on a monthly payment you are willing to pay less than what you qualify for, contact an insurance company to find out an estimate of home owners insurance for that value in the area's you are interested in purchasing the home. You should also contact the assessors office to see what the property tax would be on the property annually. You could also contact a few closing attorney's in your area and get a fee sheet of what they charge. Now that you know the type of loan, insurance estimate, property tax estimate, closing cost estimate you will have an idea of the amount of funds you will need to work with. If you are short of funds you can always get your Realtor to request the seller to pay a specific amount of your closing cost in your purchase agreement. Remember if they are paying some of your closing cost they will be more likely to not go down as much off of the listing price.