And just in case anyone thinks I am being unfair to our professional friend do the maths on this.
He says that you should buy a new domain name for every free site that you build.
The expert free site builders turn out a free site every day. So that is at least 7x$9.00 - to keep the figures nice and round for each week.
That equates to a cost of over 3k for the first year just for domain names.
For the second year you can double that figure because you have the renewal costs for all those domains you bought in the first year plus the cost of 365 new domains for the second year.
Now you can see why smp's advice is not even worth
I've been building free sites on a regular basis since 1999 - I have precisely 3 domain names that I use for free sites. I have numerous free sites on page one for various good SE terms.