Yes, both Ocerra and Freshbooks offer a Free Trial.
Ocerra is designed for Large Enterprises, Medium Business and Small Business.
Freshbooks is designed for Freelancers, Medium Business and Small Business.
Pricing for Ocerra Starts at $49/Month whereas for Freshbooks Starts at $8/month when monthly.
Some top alternatives to Ocerra includes Moss - Spend smarter, Tipalti, Pleo, Precoro, Payhawk, Freshbooks, AvidXchange, APXPRESS, Paypool, MineralTree Invoice-to-Pay, SutiAP, Bill.com, InvoiceWorks and Enverus OpenInvoice.
Some top alternatives to Freshbooks includes Quickbooks, Xero, Zoho Books, FreeAgent, QuickFile, HoneyBook, Zoho Invoice, Busy Accounting Software, QuickBooks Desktop Pro and Wave.