Good advice.
I will say that I see or receive probably 100 forge questions a year. Most of the time they all want one tomorrow, and usually plan on making something very low quality.
If someone wants to make and HT good quality knives, it behooves them to use a good forge. A simple very good forge can be made easily for about $100. A superior PID controlled forge can be made for about $200. These will last many years with no issues, and can be sold in a flash if well built. The only draw back is you will have to make it yourself and take maybe a month of weekend work to do it. It will require some simple welding, which can be done by most anyone with a stick or wire welder.
Every part can be bought from HTT, and a lot of what you need can be fund by some scrounging. If you don't want to build a burner, Atlas sells them complete with regulator for a very low price. If you don't want to go with PID control now, it can be added later ( but it would be good to put in the TC sheath).
I suggest anyone wanting a forge wait until they understand how they work and what makes a good one before ordering or making one. Reading the stickys about forges, PID control, and doing searches on forge builds and design. This will equip you with the knowledge to make either a good decision on what to buy, or what to build.
NOW, I am going to tell you what I tell 90% of the new makers who ask about forges - "You Don't Need a Forge!"
Forging is fun, and with time and skill it may save a buck or two, but virtually all (99.9%) knives end up being stock removal. A good set of hand tools, five or six good files, a big stack of sandpaper, some workable knife steel (1084 or similar) and a 2" wide belt grinder ( usually a 2X72), are what you need.
HT is best learned later on , as is forging. If you can't make a good knife in the finishing steps, what you make by forging won't matter. Since forging is a skill by itself, adding that to learning how to make knives is just going to make things worse.