Free: Contests & Raffles.
Honestly, you are doing exactly what most people would tell you to do as far as preparation goes. You might be able to get some tips from guys regarding those units but good spots are hard to come by so sharing of those is generally very limited. I also think there is something extra fulfilling about putting in the work and finding your own honey hole. That sense of accomplishment is worth the effort.
I'd say you are doing it right, I wouldn't hesitate to knock on some doors this time and year and offer to do some summer chores for access.