1) SEMrush - I believe that among all the 3rd party software, SEMrush has the largest keyword database. Their search volume data is pretty accurate and aligns with the Google keyword planner. Also, based on the type of content that needs to be produced (i.e. informational, transactional, etc.), one can utilize different filtering options available in it.
Here’s where this tool’s value really comes in: Keyword Tool has keyword research tools for multiple search engines, not just Google. If you want to do keyword research for YouTube, Bing, Amazon, the App Store, or eBay, they’ve got keyword suggestions (and data) for you. If YouTube videos, for example, are a central part of your marketing strategy, this could easily be worth the money.

"I rarely get excited about SEO and SEM tools...But, when it comes to keyword research it is virtually impossible to produce a quality worksheet without software. When I have to perform the same task for my customers, the process is even more daunting and time consuming...there is now a better way to manage huge keyword lists and this tool is called WordStream."
This tool was originally created to carry out keyword research for paid campaigns using Google's AdWords platform. However, it can also be used to research organic keywords, providing estimated global/local monthly search volumes for keywords (i.e. their popularity) and their competition (i.e. how difficult they are to rank for) for organic search.
Google has introduced Google Suggest in 2012. Google Suggest is typically used as a live feature while a user is typing a search phrase into the browser or google website. Google Suggest uses the organic search input of billions of users and try to "guess" that way what a user might be searching for even before he completed entering the query or all the words of a keyword phrase.
Long Tail Pro is a great keyword research tool that allows you to make a profit quickly. It helps dig out the right keywords to build your business and beat your competitors. If you are looking for software that would help you to make your money easily and quickly, look for Long Tail Pro. Moreover, it is stress free, as you can just make your money without stress and significantly reduces your chance of failing in your business. You can always consider yourself a winner before you even start.

The objective of keyword research is to generate, with good precision and recall, large number of terms that are highly relevant yet non-obvious to the given input keyword.[2] Process of keyword research involves brainstorming and the use of keyword research tools. To achieve the best SEO results, it is important to optimize a website as well as backlinks for the most relevant keywords. It is good practice to search for related keywords that have low competition and still a high number of searches. This makes it easier to achieve a higher rank in search engines which usually results in higher web traffic. The downside of this practice is that the website is optimized for alternative keywords instead of the main keyword; main keywords might be very difficult to rank for due to high competition.[3] There are three essential concepts to consider when conducting keyword research. Good keywords are closely related to the subject of the website. Most search engines use an internal quality system to check website relevance related to possible keywords, a non relevant keyword is unlikely to rank well for a website.[4] Good Keyword that are highly competitive are less likely to rank in the top. Keywords that have no monthly searches generate no traffic and therefore are useless for SEO. Keyword stuffing in a web page should be avoided.
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.