There's a huge difference between a landscaping company that's just starting out, and one that's been on the market for a long time and has built up a solid amount of experience. This should be obvious in general, but you'd be amazed how much more a good landscaping company can do for you when it comes to creative designs and utilizing their resources efficiently. If you're looking to transform your lawn into the best garden you could possibly have, then you should hire the best landscaping company your current budget can afford, and get them to set their creativity loose.
There are several factors you should use to judge the work quality of potential companies that you will come across. Obviously, price is going to be a factor - but it's not as indicative of work quality as you might think. Some of the better landscaping companies out there can offer their work surprisingly cheaply if you catch them at the right time, particularly during off-season months. If you're willing to get your garden done at a more unusual time of the year, this can work wonders for your budget.
Previous work is an important factor that you should focus on, if you want to get predictable results. Even if the company's specialists seem like they know what they're talking about, if they don't have any experience behind their backs, you can't be sure that they'll actually do the job in the way they're promising. Things can always go wrong in such projects, and only an experienced company would be able to adequately predict those pitfalls and know how to avoid them. Additionally, if something does happen, a good company should be able to resolve the problem immediately, without wasting your time and/or resources unnecessarily.
Long-term support is another reason why you may want to go with a company that's been on the market for a while. Since they've completed a few projects already, they'll likely have a good idea of how their schedule should ideally work, meaning they will be able to provide you with good ongoing services instead of focusing on developing gardens for their other clients. This is a common problem when working with companies that are still new on the market - it's important for them to expand their area of influence, which means taking on new clients, which in turn means that they aren't able to allocate too many resources to providing care for their previously completed landscaping projects.
Sure, you can always hire a different company for the landscaping part, but this can create additional complications for you, especially if the original landscaping project was implemented with unusual plants and/or other features. So, ideally, you should make sure that you can hire the same company for ongoing maintenance before contracting them for a landscaping job in the first place, if you believe that you're going to need the continuing support of course. Because in some cases, you will be perfectly fine taking care of your lawn on your own, without any additional professional help.