It sounds like you already have your mind made up that this will work for quite some time. Not really even sure what the question is. You can make anything work. I used to work out of a truck bed too. Need ten yards of mulch? Make five trips!
I then upgraded to a HUGE 6' by 10' trailer and became way more efficient. Biggest mistake there was not going to the 7' by 16' that I have now.
Guys are here telling you to get a trailer, I say the same. We aren't in trailer sales. We are telling you this for a reason. Buy a used one, if it doesn't work sell it.
What is your objection to a trailer? You just don't think you need it? Storage? You can do so much more with one.