Normally, if she has paid the amount due on the judgment and had a sucessful rental history since the eviction, it will over ride the eviction notation.
She may need to rent from a private landlord rather than a large corporate run apartment complex. I have found some of the apartment complexes are less forgiving (I'm a Realtor and work with tenants too).
If she hasn't paid for the eviction judgment and hasn't had a excellent rental history since, then she needs to address the issue. 4 years is plenty of time to have re-established a good rental payment history. Most individual landlords would overlook the prior eviction with a letter of explanation and a good rental history post eviction of 4 years.
Another thing she can do is pay first month, last month and security deposit. Sometimes additional months up front work to overcome the hesitation by a landlord. Remember, the landlord is most concerned about the tenant moving in and not being able to pay rent so if she can show she has been paying rent and her income is enough to continue to pay, then she can overcome this hurdle.
I don't know if she can get the eviction filing vacated or not. Check your states' statutes or check with an attorney in your area.
