In the digital age, your writing skills are more important than ever. It is easy to convey emotion and intention when you are speaking to someone in person or on the phone. While these phone skills are certainly essential to being a good salesperson, it is equally essential to develop your writing skills. These few sentences you type are often the first point of contact with a client and the primary source of follow-up. The impression they leave is representative of you and your dealership. So what does your writing say about you?
Lets look at an example I've created using common mistakes:

I've got a great tip for you!!!! There is awesome deals happening at Blank Automotive and I had to tell you. You wanted a car before when we talked, so maybe you still want one now. We have more and more deals gonig on. My manager says I can give you a great deal and I hope you will call me back. Looking forward to hearing frm you!!!!
Joe Smith

This guy's writing says, I don't remember much about you, I don't really have a valid reason to be contacting you, and I may be 12 years old.

First, serial exclamation points are completely unnecessary. People often try to use these to show emphasis on a sentence, but think about what an exclamation point is- it is a punctuation mark intended to show excitement and emphasis. Using 4 or 5 of them looks childish.

Disagreement between singular and plural is a very common mistake, such as "There is awesome deals..." In this case, "deals" is the subject performing the action "happening." Since the subject is plural, the sentence should read, "There are." Just always think about which word is performing action and it will help you to keep this straight.

Misspellings are very unprofessional. Read carefully and download an automatic spell checker into your browser. With browsers that can automatically flag misspellings and e-mail programs with spell check buttons, there is no excuse for these simple flubs.

The feel of the e-mail is overly casual and juvenile. Why is this?

There are a few reasons. The most obvious one to me is sentence structure. All of the sentences have a similar length and a simple structure. Try throwing in compound sentences to change it up a bit.

Word choice is another reason. "Awesome" can be a fine descriptive word, but when combined with small sentences is sounds like something Ted Theodore Logan would say (Bill and Ted anyone?). There is also a vagueness to the entire e-mail, compounded by overuse of the word "deal." Overusing any one word is a definite no-no. And what is a deal anyway? Perhaps a deal is $1000 over invoice for one person, $100 over invoice for another, or $500 off sticker for someone else. Try to be more specific without giving away the cow with the milk.

Finally, there is nothing really personal about this e-mail. The customer's name wasn't used, their desired vehicle wasn't referenced, and there was generally a very careless feel.

Let's look at a better version of this e-mail.

Hello Marcy,
I've got a great news to share with you! Blank Automotive is having a tent sale this week and I had to make sure you knew. Last time we talked, you were looking to purchase a Nissan Rogue in about two months. I know it has only been about a month, but I thought perhaps you would be ready to buy if the deal was right. I'm able to offer you a cash-back rebate from the manufacturer this month and when we couple it with the tent sale this weekend, it may be a deal you don't want to pass up. I'm happy to schedule a test drive with you. I'll follow up with you before the weekend to see how your schedule looks, but feel free to contact me in the meantime with any questions!
Thanks,
Joe Smith

This guy's writing says, I remember talking with you, I don't want to bug you too much because I know you said you weren't ready, I care about you getting the best deal, and I'm a professional who respects you.

Notice how sentences lengths are varied and specific information about the client is used. It feels personal but professional. There is specific information about why she could get a good deal without giving exact numbers.

If you need help on developing your writing, there are some excellent books out there to help you.
I recommend "Grammar Girl's Quick and Dirty Tips for Better Writing" by Mignon Fogerty for a lighthearted feel, or "Fundamental of English Grammar" by Betty Schrampfer Azar for a traditional approach.