If you're interested in scale length, rings etc. put a thread in the builders forum that one should be able to give you some answers.

There's no consolidate buyer's guide I'm aware of because banjo makers and models come and go, and once you include used banjos (which you should do) the list explodes to be "too much".

There is literally a plethora of "grow into not out of" bluegrass banjos in your $2000 budget. An embarrassment of choices.

One entire category is known as "Masterclones". Banjos (mostly made in Asia) that look like Gibson Mastertones in design, execution and decoration. Since about 1970, first Japanese, then Korean and now Chinese makers have flat out copied Gibson Mastertones to the best of their understanding and execution. If they are nickel plated and carry some kind of Gibson-like inlay and finish colors, you just have to experience them personally to determine WHAT YOU LIKE. Brand names include Tokai, Gold Star, Iida, Fender, Epiphone, Gold Tone, Morgan Monroe, Alvarez, Kentucky, Saga, Recording King, and MANY more. The oldest ones are generally Japanese. For a short middle period they came out of Korea around 1990. Then China kind of swept up about ALL of the instrument building business. A few Chinese companies had American experts who moved to China to set up factories, train workers, handle inspection, etc. And their banjos have been as good as the best of the early Japanese. Lately some of these companies have been run out of business by economics, tariffs, failure of owners, etc. and the brand name has been sold or picked up by other makers who are trying as of this date to step in. You can study Asian Masterclones for the rest of your life trying to find what you like best. ALWAYS play such a banjo before buying!! Looks/price aren't everything, a lot of power plant of a banjo is hidden and required either disassembly or personal knowledge to understand. Meaning, if you have questions about a SPECIFIC Asian Masterclone, get photos, description and provenance and ask specific questions here.

Asking for a complete buyers guide just ain't gonna get you much.

Another category is vintage American brands from the 1960s/70s, which I harp on all the time. They are in your budget!!! First would be Gibson Mastertones from the late 1960s, 1970s and first half of the 1980s. Not Gibson's best period, perhaps their worst, but some of these banjos are perfectly fine professional instruments (if not best quality) and prices are right in your wheel house. The other 3 big American brands were Fender Artists made in California (generally excellent quality pro instruments), Vega who had 3 reasonably priced pro banjos (Pro, Scruggs and VIP) and a few also made after 1970 by Martin who bought the Vega company and parts and for a few years offered Vega-by-Martin, which were fine banjos. After that the Vega brand was sold to an Asian company called Galaxy, and you have to be careful about them because the banjo designs changed a lot. Finally a FINE US brand was Ode, or sometimes Ode/Baldwin, Style C, a pro quality instrument that was played by some top players in the 1970s and 80s. You can afford these instruments.

Finally, there are LOTS of boutique banjo builders or banjo kit suppliers who have put out fine instruments, although not a lot is known about them, from the 1960s to today. Some of them are in your budget. Again if you find a specific banjo, get photos and ask questions here.

The biggest thing to be careful of is "parts banjos" which individual entrepreneurs have pasted together from parts on the after market or repair market or substituted from name brand banjos. It's hard to price a collection of parts ESPECIALLY if the seller hasn't been forthcoming about his sourcing. So many potential buyers have sent photos of banjos to the BHO for advice, and so many times it has come back "it's an assortment of parts with a Gibson tailpiece and armrest", but NOT A GIBSON. Or the like.

Read the BHO classifieds and see what people are offering for sale. Read the Collectors and Shopping Advice threads. If you're into Gibsons look at Greg Earnest's web site with photos and descriptions. On BHO you'll encounter Gibson experts and retirees, Recording King experts, Saga/Gold Star directors, Gold Tone managers, Ode and Baldwin/Ode experts, Fender experts, Tokai experts and on and on. Usually someone can offer you some advice.

Stop in every music store you encounter and try every bluegrass banjo they have. Find out where your taste lies.

But don't spend more time finding a banjo than you do learning to play the dang thing!!!! Perfection is the enemy of good enough.

Don't be afraid to buy used. Go to the Marketplace on the left side of the screen and click on it. If you scroll through the banjos for sale and find one you think you might like, get on here and ask questions about it. You will get plenty of help.

There are a lot of factors that go into understanding what you might want, and I can't think of a single resource that will answer the whole question for you. However, I can pretty confidently say that if you want classic bluegrass tone you'll want a resonator banjo with a brass/bronze flathead or archtop tone ring.

If you're determined to buy only once I would spent a decent amount of time playing lots of banjos and researching.

This was a vague answer but I'm happy to answer any specific questions! I recently ended a long journey of buying/building different banjos based on tonal factors I wanted to manipulate, so I have an informed opinion on most parameters regarding bluegrass banjo construction.

For me I spent $100 on my first banjo. I thought I wanted to play bluegrass, and someone cautioned me to not spend much on your first one. That was good advice since I found myself more drawn to old time fingerstyle with a completely different banjo.

Just my experience.

Whatever you end up getting, with a $2000 limit I'd buy something used. More banjo for the buck.

The preferred banjo for "classic" Bluegrass is a flat-head Gibson Mastertone or Mastertone copy, such as a Gold Star or a Gold Tone "Twanger". Independent luthiers have also been building Mastertone copies in their basement workshops for the last 6o years. Some of those banjos are better than genuine Gibson Mastertones, but you have to know what you're doing to get a good one.

Wow!

Thanks everyone! Funny ..... as I've played guitar for years...even electric and can tell pretty much what someone is playing. So if you want to sound like Hendrix, Strat and Marshalls.

While I can tell the difference in banjo playing styles and know types of banjos used between old timey and bluegrass the best bluegrass that I dig just sounds good and I can't tell the difference between what kinds Scott Vestal or Sammy Shelor or any number of banjo greats may be playing.

I totally get a myriad of subtleties and adjustments that can be made not to mention players talent. The Start/Marshall set up wont make you sound like Hendrix but it will more than a Tele and a Vox!

I need to find a shop or two that has a variety.

Thanks!

Sammy Shelor plays a pre-war Gibson RB 75 flat head Mastertone, and/or a Huber-made repro of the same banjo too.

I'm not sure but doesn't Scott Vestal play a non-Masterclone? It has a peghead shaped about like a stick. Nechville? Someone here will know.

Scott Vestal plays a Stealth which he designed and built through Robin Smith.

The difference with banjos compared to electric guitars is there are more potential setup choices that change the tone considerably (mostly head tension and bridge weight). Probably 90% of bluegrass players play a banjo with a maple rim, bronze flathead tone ring, and a frosted head, so most are working with the same tone producing parts.

I’ve answered similar posts this same way. My first professional level banjo was a Deering Sierra. Simple basic pro banjo, with the same tone ring as their high end blingy banjos. I got caught up in the bling banjo and G word banjo hype, and sold the Sierra to finance several banjos that I didn’t like as much as the Sierra. I always missed it. Over 20 years later, I bought another older used Sierra, and this time I’m never letting it go. Knowing then what I know now, I would still be playing that first Sierra, and not wanting for anything else. A used one is well within your budget.

biggest difference in the final sound of a electric guitar and a banjo is the electric guitar plays as much on the amp as the guitar.
a banjo final product depends on the hands more then the mic..
we call it pulling tone ... some are great at it and some not so great.
it didn't matter what banjo earl played , he still sounded like earl.. and as far as sammy goes, a lot of his lonesome river band stuff was on a top tension pre war and his 75.. still sounds like sammy on both. 

 if you go back  and listen to some old scott vestal when he was with larry sparks ,, southern connection and doyle lawson and quick silver you can tell its still scott but all those recordings were before the stealth banjo... all be it he did start leaning more towards melodic in the mid 90s.                                                                 

  if possible find one you can play first,,, you have have to feel right with the banjo and love the sound. if you don't you will still be looking,, but 2000 bucks broker.