A home study can be extremely fast or can take up to six months or more. It is up to you to collect all your verifications and get all clearances that will be outlined on the checklist. I have had people begin a home study in the past and turn in half of the verifications and then stop all contact for six months. This makes me wonder if adoption should be explored more as maybe there is something that is stopping you from pursuing an adoption. Before you begin your home study, you should be completely ready to spend the time needed to collect the needed documents and make the home study visits. Documents and verifications can expire if you get them and then take six months to get the last verification to your home study provider.
It is recommended that clearances are done last as a baby cannot be placed in a home where even one clearance is out of date. For example, If you get your local law enforcement clearance first and hand in you last verification a month later, your home study will be dated after last verification is received, but the local law enforcement will be out of date a month before date of home study. You will have to redo the clearance if your baby is placed after clearance is received. After your home study is complete, you should keep track of the clearance dates and expiration date to be ready to do an update if the need should arise.