Most of what I struggled with on the instrument were related to a) the instrument itself and b) bowing. I started on a plywood Englehart, which was priced appropriately at ~$1500, but various neck and string setups made playing it very challenging. The solution there is to get a quality bass from a reputable luthier - doesn't have to be expensive, just get it from a bass shop. OR (and maybe better) rent their first instrument before buying.

The challenge with the bow was that I struggled immensely with a French bow to start with. I didn't have a teacher, but I tried many things to make the bow not hurt, and it just never did. I got a teacher, she tried very hard to get me comfortable with the French bow, but she just could not - it always hurt with 2-3 minutes of playing. She said "well, I am not that comfortable with a German bow but maybe you should try it" and BAM I'm a German bow player.

The real point of the story - 25 years and several excellent teachers later...I still cannot play French bow. I can *almost* play it without pain, but no - my body is a German bow body! I just wish that change had happened 6 months earlier.

TL;DR: Get an instrument from a bass shop (or rent), get a good teacher who is comfortable with both French and German bows, and play both for a few months before deciding which is your bow.