As long as the current relaxed visa waiver scheme goes on, not much point to spend extra money on the broker.
In the past, I have relied on those agents a few times though.
After September 2006, Thai immigration started to become much less friendly toward the long term visa-waiver(visa run) expats. Saying no continuous stay more than 90 days out of 180 in a year(in case of visa-free entrants).
Then a lot of peoples started to switch to Tourist Visa(from Thai embassy in the neighboring countries).
Eventually, Thai embassies started to limit the numbers of the Tr Visas they issue to one foreigner.
I actually know someone who got No More Tourist Visa To You Stamp on his passport back in 2013.
And it turned even worse after military takeover in the summer of 2014.
Visa-waiver entry was allowed only Twice in One Calendar Year.
They also started to demand additional papers to apply for the Tr Visa at their embassies as well(return ticket, hotel reservation etc).
That practice went on till the end of its regime in 2023.
Compared to the 2008-2023 period, their visa policy changed completely as you can see today...