This is a big question that seems to have no correct answer. The answer to this question is based on individual builders. Just because you’re getting a good buy on the home does not mean that you’re getting a good buy on the floor covering. Normally the standard floor covering is extremely inferior. They will put down thin carpet and miniscule padding. The tile is usually a standard tile that all of the builders use or whatever the tile store is having a close-out sale on. Keep in mind that this may vary from builder to builder so make sure you know exactly what you’re getting. Allowances or credits for getting your own flooring will also vary from builder to builder. Generally you have 2 options with flooring.
The builder will probably offer several upgraded high quality flooring packages but you will pay more through the builder than you would pay if you bought the same quality flooring on your own later. The other option is to get the builder to credit you for the standard carpet and you put in your own carpet after closing. Of course, it is always easier to just let the builder deal with it, so you have to decide if it is worth it to you to save a few dollars. The areas that must be covered with flooring to get a Certificate of Occupancy (CO) vary from location to location. Know the local laws! It’s a pretty good bet that at least the bathrooms and laundry room must be covered to get the CO.
If you are going to get your own flooring later, cover the mandatory areas with the cheapest material possible like linoleum. Here is a trick I have learned over the years. Ask the builder not to glue the linoleum to the floor saving the labor costs to have the temporary flooring ripped up. The same rules apply to other items such as appliances. Many times the refrigerator will be way to small for the house you are buying and the dishwasher is substandard. Over the years we’ve seen appliance packages vary from very substandard to adequate. Pay close attention to this detail. Some builders will give you a credit for appliances that you don’t take so you may want to take the credit and buy what you need later.
Beware of low ball Home Owners Association dues. Builders generally artificially keep the maintenance fees low while the community is being developed. For example the builder might be spending $150 per lot and only charging $49.95 and absorbing the difference while the development is being built.