mrusk,
If I can make a suggestion....find a great freelance landscape designer...the client is to pay the fee for the design.
You are going to always have problems going about it your way without a plan. (That's a plan for yourself, not a landscaping plan

)
If you don't have a plan, you can't estimate correctly.
If you pay an LA, that will always be money out of your pocket that you may lose.
If you create a plan and it is not your strong point, there will be others out there with better plans.
I used to live and work in New Jersey, where I see you are. I worked for a Design/Build firm in northern NJ...actually I was a sub-contracted designer. He met with the client, gave them some exciting visual ideas, and then told them to get a professional project, they MUST have a plan. He went on to rave about me (to get the job, I am sure) and I am sure he sold just as many jobs as the typical landscaper, if not more. He had the client pay for the design. Nothing out of his pocket. If the clients are going to spend money on a project, the design is just a small percentage.
Hmmm..what do do about those landscapers who did a design for free. I remember them well. Ignore it. Be a great salesman. It will happen sometimes, and other times the client will see the value in a design...if you sell it that way and believe it. A design that has to be paid for will be of such detail and quality.....well, that's what you say.
Bring one of the designs along (one of the great designs that will wow them).
Susan