It is always a great idea to read testimonials and get references before engaging professional services. However, testimonials are prohibited by the Security Exchange Commission for financial planners/advisers – and for very good reason. Financial advisers cannot advertise how much money they can save you or make for you, particularly if they are investing your money on your behalf.
Though I do not manage your money or sell products (I have zero conflicts of interest), I still fall under the same rules.
In lieu of testimonials one thing you can do is check them out at FINRA to make sure no complaints have been filed against them. The website is https://brokercheck.finra.org/.
Just put in my name, Robin Lynn Gordon and it will show no complaints have ever been filed.