HI there, have you taken a refresher course (or are you required by your state)..or have you kept your license current?
I have worked in a variety of agencies..first as a CNA, then LPN, with just a little bit as an RN.
Each time, I felt the interview and paperwork process was straightforward and pretty easy. I had previous CNA experience before signing to agency..a good portion of agencies will not accept new grads or returning nurses , or nurses who do not have current acute experience, but rules vary. I worked for an agency as CNA while I was in nursing school..at the time jobs were plentiful

I was mostly sent to long term care facilities. I grew comfortable with ltc ..the agency who employed me as a CNA later promoted me as an LPN once I was licensed, because they knew me well and I was already familiar with ltc.
My first day on the job as an LPN was VERY hectic and stressful. I'm not sure if it ever got any easier ..but I did develop familiarity with certain ltc's that I was sent to over and over again. So that was helpful. Working a new facility is always tough. I really think what saved me was my previous experience working as a CNA in ltc , and I was familiar with how agency worked.
Once I received my RN license, I still worked at the LPN level in agency as I was looking for an RN position (got one in hospice).
Again all agencies are different but once your paperwork is finished, verified, drug screen, CPR, TB, the normal stuff..then the agency calls you and asks if you want to work various shifts.
In the past I was never given orientation when I went to a new facility. However I just signed with an agency in Hawaii, and what I like about this agency is that each facility requires a nurse to come in and orientate (not sure if it's paid or not).
You can accept assignments and work in to your schedule..the more flexible you are, and as you prove yourself to be reliable, you will be given more assignments. There are times of high and low census so be prepared to have a reduction in hours at any time. Also, if you badly need hours, be willing to be placed on call in case something comes up.
A downside is that you can get ready for work, have daycare arranged, and get called/cancelled an hour before your shift. I have been on my way to a facility (in the past) when I was cancelled.
Good luck!
ps I cannot comment too much on agency for hospital work
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