Well I can give you some general info. The most common truck washes you see are basically hand wash operations. Chemicals are applied with sprayers and then a combination of hand brushing and pressure washing. Very labor intensive. Moving up the food chain are drive through arches. As the truck drives through a series of arches, chemicals are applied first, then high pressure blasters, and usually a spot free rinse. Does not require near as much labor, but now equipment costs start to escalate. This also starts to get a little tricky as some chemicals that are great for cleaning can also do damage to some types of polished aluminum and chrome. Next up the food chain are automatic rollovers. You will mostly find these in
fleet operations where mostly the same type of vehicle is being washed. It's easy to wash a school bus but not so easy with a tanker that uses polished aluminum. The real key to every one of these methods is the chemicals. You can't swing a dead cat without hitting a
soap salesman in many places. Many try to sell on price. Stay away from them. Some contain deadly, and I mean deadly, substances. Stay away from them also. I have been fortunate to have met some really good people in this industry that are about to come out with products that will clean safely at an affordable price.
Now the nuts and bolts of it. You will need a lot about 3 acres, little more the better. It HAS to have city sewer available. You can use city or well water. Location is the same for any business. Good visibility and close to a truck stop. You should plan on two wash bays, a large equipment room, and office. Other things to consider for the site are an interior trailer wash and a detailing service. This is not as simple as a carwash. I own and operate a self serve with an automatic by myself. You will need people there (don't even think of an unattended operation) for probably two shifts a day seven days a week. Even if you do a hand wash operation you will still end up spending well into the seven figure numbers.
OK, now the good news part. You have identified an under served market. Where I'mat in south FL there isn't a truck wash within a hundred miles. Let's play with conservative numbers. You should be able to average 4 trucks an hour at a hundred a pop, so in a 12 hour day that is 48 times $100. That is $33,600 per week. Now we're talking serious numbers. If you are really serious about this I suggest going to a truck wash and work there for a week or two. You'll learn a lot. Getting into car washing with no experience can be real, real frustrating. With truck washing this increases exponentially.