I have been an Interior Designer for over 15 years, from Residential, Commercial, Institutional, clients with all kinds of budgets, styles, time frame but, what makes my job go smoother is that I always ask tons of questions before I start so my top 3 are:
1- Have you worked with an Interior Designer before? The reason why I ask is that they will have someone else, that is not emotionally attached to the project, someone that will be seeing the project from the "outside" and it is very important that the designer have a clear vision and express themselves very clear to the client, otherwise, the project can become delayed and clients might get frustrated. The second question is:
2- Have you done any remodeling/ new construction before? It is imperative that you, as a designer ask this question on the very first time you meet/talk to the prospect client. This will help you not just walk your clients through the process but when you send them the questionaire you need to be more specific with the questions. Las question is:
3- Have you done your research and what are your favorite stores/brands? That should be part of your 30 minutes first time consult, asking that question will help you identify the clients taste, budget, priority. We know that the master bathroom is the most value part of the home is but in case they want all things discontinued/cheap, make sure you tell them and do what they want to do. They are the ones living there not you, but, in case they want to sell one day, they are the ones that will suffer the consequences.
I hope that was helpful, in case you are going to start a new project, feel free to contact me. I can travel and I do offer consults online.