Question on where, how to help advertise a product to (mainly) Owner/operators.

I am new here. Part of reason (other then to gripe) is a friend of mine is expanding his business (making custom sleepers.) He makes a dang good unit. (IMO) and bought a MUCH larger shop......
So (as to not violate what I recall of TOS here) I will not give name, website,etc (unless asked by PM/E-mail/respond in kind)
Here is question. What do you (as Truck drivers/owners consider the best way for him to get his business out to where you can see it? (and not cost a fortune as keeping overhead low is why he underbids (the big companies) and has a wider unit with IMO a better ride/insulation....
He had articles in trucking magazine couple yrs back. (when he was doing 1-3 a yr) He does get a little carried away with everything being perfect. I showed him a couple areas to cut corners. He won't, had good reason why he does it right.

There is a "North Central Truck Paper" that has @4"x5" pic ads for businesses. $100 a week. If it was private party/truck/trailer for sale it would be $250 for 4 weeks same size add...
The overdrive type stuff are in $10 GRAND area. :0

So where is best "bang for the buck" for folks who want (what I call) a "RV instead of a sleeper" Its wider/(can be) longer, better insulated, set up right in $40k+ with sink/shower/stool/stove/TV........

Thanks for any help.