Buying a home is a huge investment that you want to protect in all ways. When you buy a home that already has a tenant, you have a legal issue to worry about. Whether you want to let the tenant continue living in the new home you bought as a renter or you want the tenant out, you can't just continue with your purchase on a verbal agreement with the person living there. You need a real estate attorney for many reasons; here are just a few of them.
Your tenant has rights
If you have a tenant in your newly-purchased home and you want them to leave, you can't just tell the person to move out even though the home is yours. Your tenant has more rights than you think and will require notice to move out. You may not even receive rent in the meantime, meaning you're dealing with a squatting situation. You should get a lawyer to help encourage your tenant to move out so you can move into the residence. Or, if your tenant has agreed to move out but hasn't done so yet, hire a lawyer to ensure the moving process continues as agreed upon and nobody is breaking the law in the meantime.
Your tenant may have a contract
Did you read the fine print when you bought a home that has a tenant in it? The tenant may have a lease that goes into the time frame in which you've purchased the home which means you are now the landlord and can't kick the tenant out or ask them to leave without cause. If you want the tenant to stay, you'll need to understand their rental agreement, which your real estate lawyer will do for you.
Your tenant may destroy your home
Something you may need to worry about is this: your tenant may destroy the property you've just purchased because they know they have to move out. They may accidentally break windows or damage walls as they move out of the home, or may purposely cause an issue in the moving process because they are angry with the previous homeowners for selling the property they were living in. At any rate, having a real estate lawyer to manage the transfer of the property to your ownership while managing the actions of the current tenant is a good idea. If all goes well, you should be in your home or able to rent the property out in a short time.