^^^^THIS^^^. About this time last year by boss told me he wanted to start a "drone division" at work and asked if I was interested in going to a class to get licensed. The first UAS I ever flew was the Inspire 1 the instructor had for class. Man I was nervous as heck. As soon as I finished the class I bought a Phantom 3 Standard since I knew my department was ordering a Phantom 4 Pro + for me to fly. In the month between getting licensed and our P4P+ being delivered I had the chance to fly my P3S a dozen times or more and practice some of the basic things I learned in class. I got comfortable flying my little $400 P3S before I ever got to see the nearly $4000 P4P+ kit with all the extras we got at work.If it is in your budget, also buy a P3 and play a lot. You will enjoy flying, be more relaxed and culminate your skills. If you get bored, sell it or give it away.
Sure the P3S doesn't have all of the sensors and obstacle avoidance but that can be a benefit. It Will run into stuff if you don't fly right. It requires you to pay a little more attention but at the same time it is less stressful since you know that if it does crash it is only a fraction of the cost of the P4P. I actually enjoy sitting in a chair in my driveway just cruising around a warehouse area near my neighborhood with my P3S compared to they flying I do at work.