There is too much to discuss and not enough information.
When I was a full time salesman, I was paid 25% of gross profit on each of my job, but I was more than just a salesman because I managed my projects as well. If I sold at my bosses price, it broke out to be 7% of the sale price, but I hardly ever sold as his minimums.
I pay my sales people at 11% of the sale price plus bonuses for hitting monthly targets. I pay zero salary. My sales guys sell residential roofing, siding gutters and windows. Quick easy jobs, also quick easy sells IMO. There is no managing of the production involved on their part either. I personally feel I compensate very well.
I have supplied my sales guys with price sheets for everything and leave zero guessing to them. I have also designed measurement sheets which directly correspond with the price sheets. It's very hard to make a pricing mistake unless they measure wrong. I have also written lengthy verbal presnetations and put together detailed presentation books with pictures etc... These are to be used as guidelines for the sales guys, but never to be used a canned pitch.
I also have base "systems" which I have put together for everything we do, which can be altered however the salesmen needs to write up a work order explaining to production exactly what needs to be done. Basically they just copy and paste the proposal and add any details that production needs to know. This way everyone is on the same page and the jobs run smoothly and there is no guessing... and if there is a question, the salesman's number is on the work order and the foreman calls him and asks.
If you are doing commercial work or building houses, or major remodels, I have found most guys are paid a salary plus a low commission. The sticker price is usually alot higher than the roofing siding we do, and usually take longer to close.
Will your sales guys also do the stimates and the managing or just the sales? I knew one company who had an estimator who did the print take-off's then a sales guy who "closed" the sale then a project manager who managed the project. Seemed very cumbersome to me to be honest.
As a previous poster said it could be a great investment or a huge loss. I have found most "Salesmen" aren't worth squat. There is always some craaazy drama involved with them. I had a huge loss in regards to salemen last year... I went through 5 before I found one worth keeping then as it turns out he had a drug problem and owed back taxes and child support.
This year I have trained someone who has zero sales experience, but has hands on experience and it's been working out so far.