Most of my businesses utilize Freshbooks and then convert to Quickbooks Online when they have established a cadence. Freshbooks is a nice place to start because it's cheaper and easy to use and then when you end up getting more deal flow you can change over to QBO for a more advanced integration between bookkeeping and AR. This approach allows you to get inbound revenue easily and in an automated fashion while you construct your chart of accounts and then can switch over to "real" accounting.