I am sorry my post will be quite opinionated, I will describe my path and raise some questions to think about before you spend your hard earned dollars.
I'm talking about brand name system only here, because having a brand name -- means having support, it is common to see 15years old laser system working 5 days a week 8 hours a day.
These systems are solid [Trotec/Epilog/Universal/Gravograph], support for them is solid. you may have spare part in 3 days or less if motor is broken, or laser is not firing -- even for 15 years old system.
You may call tech support and in 15 min your question will be answered. You may drive and see your local tech representative in your are in person.
All these people you calling or meeting love lasers and they are willing to help you.
Also: brand name systems are based on metal (or ceramic) rechargeable laser tubes [brands are Synrad, Coherent, Iradion, Epilog, Universal], which lasts much longer than glass tubes, though
remember each tube is individual creature, there is no exact science on recharging the tube, and you usually get +15%(or more) on top of nominal laser power after recharge.
I started playing with lasers a year ago.
So, my advice on where to start: check kijiji.ca and craigslist.org twice a day; check searchtempest.com and searchtempest.com/kijiji as search aggregator. Be patient. Expect to drive 300 miles for a good deal.
Check Canada listings regularly -- they have very good offers regularly. Like Epilog Helix under $6000 canadian dollars.
Also you may check industrial auctions of any kinds -- online. I saw Trotec Speedy 300 [80watt] for $9500 -- it was a steal but I could not afford as hobby machine.
First thing is educate yourself, focus on brand name machine [Trotec or Epilog brand]. Learn about models of each brand. Learn why servo motors are better choice [choose Trotec Speedy300, or Epilog Mini24/Helix],
remember that cheaper models like Epilog Zing (and likely Trotec Speedy100) uses stepper motors -- you may regret having stepper motors later.
Learn why people buying bigger system if they can. Consider 12x24 is a minimum table size, you will regret having smaller table size later.
Few years after you'll get the system in your hands you will think about upgrading the laser tube, and bigger machine will accept more powerful tube because more powerful tube is usually a longer tube,
for example: Epilog Helix will accept Coherent C70A tube -- which is 70watt tube, when fully charged it may fire as much as 90+watt, or Coherent C55A tube -- which is 55watt tube, when recharged may fire 70+watt.
Look here for recharged coherent C55 tube performance
https://www.youtube.com/watch?v=lKBJJ_US-W0
Skip very old lasers, like those made before 2000 -- main reason for that is: those will not work with latest operation systems and design software [Like Windows 10/MacOS X], so
it would be real pain to send a job to a laser -- at least you need to know what software will be compatible with your laser. To my experience: Epilog line produced from 2006 is compatible with Win10.
Learn how to test the laser power with piece of acrylic -- Epilog manuals has tables of speed/power/frequency to cut material through -- refer to it, those are at the end of the manual.
You may check Universal Laser systems and Gravograph as brand name manufacturers of laser systems. To my sense software which comes with Gravograph is counterintuitive, and I cannot say anything
about Universal Laser -- the only thing I know is -- it is dependable brand name machines.
.....and BE PATIENT on laser hunting.
.....to my experience, interesting deal appears on my radar once every 2 months [like Epilog Helix 40watt under $4000], it is usually in Canada, most interesting deals appears from July till October, or
from Christmas till end of January. .... finding a good deal is a lot of work and it may be gone in 3 hours after message is published on craigslist/kijiji/ebay/industrial auctions.
When you search, you search for "Trotec", "Epilog", "Laser Engraver", "Coherent laser tube", "Synrad laser tube". When you find what you want -- do not wait, run. When you see real thing it may
be different from you thought it would be, so discuss price after you see real thing, run test if possible.
Right now on Kijiji: Epilog Helix 35Watt -- $6500 canadian dollars, which is under $5000 USD. Location is Canada/Toronto. Based on pictures it was made in 2006 or early 2007. -- that is an awesome machine. what you would need is to learn how to service it -- clean optics and lubricate moving parts --- download user manual from epilog web site, read it thoroughly -- and you'll be happy with it.
https://www.kijiji.ca/v-other-busine...ver/1460747430
For recharging existing tubes I used:
www.evergreenlaser.com -- they are awesome. you may also try photovaclaser.com -- I did not tried them yet, I saw laser tubes on ebay with photovaclaser service stickers. ask other people who used them and decide what to do.
On industrial auctions: it is interesting place to search for unusual devices. Like right now you can see Epilog 36EXT laser system 75 watt on bidspotter:
https://www.bidspotter.com/en-us/sea...rchTerm=epilog
Auction style: current bit is $5, auction ends: October 11. -- that is a very good price for this machine.
https://www.bidspotter.com/en-us/sea...4-aad5018a35dc
This system is too big for our small lab, but it may be good for you. I estimate selling price for this lot from $6000 to $7500. if you miss it, you may find same system later on ebay for $13000 or so.
You may check
https://www.facebook.com/pg/UsedLaserEngravers/ but I bet you will find better prices elsewhere.
So after a year of laser hunting....I've got the following:
1) Epilog Helix [2006] 35watt from Canada/Toronto [through kijiji] -- price too low to say, you may assume it was given as a gift. -- this unit was mistaken for old-old printer made in 2006, and sold to us for parts without testing. it works as new, though I had to drive 700 miles to get it. -- this is unicorn you may catch such a deal if you are searching.
2) Epilog Mini24 [2007] 35watt from Connecticut [through craigslist], laser tube was empty, unit is practically brand new -- $2500
3) Epilog laser tube [type C, 50Watt] with brackets and red pointer assembly from eBay -- $1200. someone was selling brand new from epilog factory, with all paperwork. measured laser power is 53Watt
Then I learned that Coherent tubes with RJ45 control socket could be installed into Epilog Helix and Mini.
4) Coherent C55A tube, recharged with laser power output of 76watt. -- $2500 [had to trade in a 35watt empty tube for it] worked with evergreenlaser.com on that, thank you Jean if you're reading this:-)
Got two MeinWell PSP600-48 transformers to upgrade systems above, was very careful with wires, breakers, etc -- yes, if you have a tube 50Watt or above -- you need at least 48V 22Amp of power -- use scheme from MeinWell web site -- single wire of current share will make two transformers work as one unit -- same electric scheme as Epilog uses.
Got an air assist Junair OF302 with tank and pressure regulator off eBay -- $180
Got Turbo Accelerator nozzle for epilog from eBay -- still available there, quite expensive [$195], but allows to cut without charring, even with 35Watt laser, while 76 watt laser makes almost white cut -- that was a quality call mostly.
Got UPS to keep my systems on the safe side and protect from electric spikes and power outages.
Bottom line: Epilog Helix now has coherent tube and fires 76 watts, Epilog Mini24 has 50 watt tube and fires 53Watt. -- spent under $8000 for both.
... and after that I gave all this treasure to my beautiful wife, she now does laser cutting/engraving [etsy link was eaten by a link eater]
and I'm very happy.
PS. If you know where to get Coherent C70A tube, working or empty -- please let me know.