Should one open up a business bank account before starting out?

[Joshua Sun]

My girlfriend and I have been saving to buy our first investment property. 

Should we talk to a bank to open up a business account? I hear it will be easier for CPA / Taxes later on if all expense from purchase, rehabs, repairs, etc are all under one bank account? 

I guess it will be a good place to collect rent as well. 

If anyone has any other advice considering where the money enters and exits, please let me know. 

Thanks!