This isn’t the only tool that mines Google Autocomplete. There’s also, but this tool restricts results to ~700 keywords (more are available for “pro” members). Infinite Suggest is another alternative, but despite the name, I’ve found that it still doesn’t find anywhere near the number of keywords that Keyword Shitter finds. And there are tons of other Google Autocomplete miners too. Just Google “google auto suggest tool” for more. There’s also this tool from SEOChat which mines autocomplete suggestions from Google, Bing, Amazon, and YouTube.

I want to ask that when you were the owner you offered a life time membership option which i think should be offered one last time before migrating to new plan.Long Tail Pro Users who had bought the software @ USD 97 and were paying USD 27 per month on as per need basis have no edge over the new users.As you are still 20 percent owner of the business so it is requested to please give old users who already owned and purchased the basic software one time life time license offer or discounted price.
To answer your final question, yes but not really. You can definitely use AdWord keyword planner tool to get solid organic search volume estimates. However, don’t just stop there. Leverage other tools to find longer tail variations you can map against various stages of the buyer journey. I like to use SEMrush, Keyword and Google autosuggest.

KW Finder is similar to the Google Adwords tool; it even pulls up similar results, which aren’t as entirely on-point as the immediate results from SEMrush and Moz. From my experience with KW Finder, the searches are a lot better if you put some time into manually adding in filters like negative keywords and additional keywords you do want to include.
"With Google giving over the home page to ads and their own properties for commercial keywords, the Long Tail keyword is more important than ever. If you have a website, you know that most of your traffic comes from keywords you never would have thought of. With Keyword Researcher, you can find them in advance and make sure that you're the one that snags this traffic. I use it for all of my e-commerce site planning."
3. Ninja Outreach: Full disclosure this is my own tool, and it is actually an outreach tool, so you may be wondering how it plays into Keyword Research. The fact is there are quite a few data points that NinjaOutreach gets for me that I find useful in keyword research, such as the articles that are ranking for the keyword in Google, their domain authority, their page authority, the number of backlinks they have, and other social and contact data. It's pretty valuable stuff, especially if there is going to be an outreach campaign tied into the keyword research. I wrote a great article with Jake from LTP showing the combination of the two tools.
The final sales price was based on a multiple of trailing 12 months net income (i.e. The average net income over the most recent 12 months).  I feel like I got a very good multiple.  I had talked to the brokers at FEinternational, Quiet Light Brokerage, and had viewed sale history of other similar companies, so I know the price I received was very competitive.