Hi, just started using quickbooks as plumber I need to send quotations to prospective customers but I can only see an option to invoice?

Hello Jackgriffith38-g

Welcome to the Community page

There is no option or feature in Quickbook Self-employed to send estimates or quotations, you can only send invoices. 

So you could create and send them an invoice and just put estimate in the description part as a workaround.