I bought a mechanical IKEA desk (that goes up and down in height), spent at least 20% less than all the other online options I found available and they shipped to me in 5 days. Knowing how to follow instructions, I just assembled it in 30 minutes and it's the desk I now use daily at home.

This just to say that YMMV based on the item you buy, where you live, what's your experience with "self assembling" items, etc.