This is a good point. Also, I would ask if there are any issues with "thread type". Certainly want to try it out.

I sold my HQ16 with ProFrame for $1,500 three weeks ago. I bought it used 7 years ago and quilted almost 400 quilts for Project Linus. The machine is all mechanical and only one oiling point (the bobbin casing area). Not a single problem. As for thread, I used everything from serger thread to industrial....basically whatever I got cheap or free. The trick is to constantly brush out the lint and learn to adjust the tension on both the bobbin and the machine to adapt for the different types of thread. I upgraded to an Avante with ProStitcher. The HQ16's new owner thought my sales price was way low. From my point of view, I wanted it to go to a good home and be a starter machine for sister quilter. I spent 5 hours with her to be sure she was comfortable using the HQ and we played with various weights of thread. The look on her face the first time I twisted the tension knob as tight as it would go was priceless. However, she walked away knowing she couldn't damage anything and tension was no big deal. She did 4 quilt tops in the first week and I got a lovely "thank you for selling the machine to me" email.

I want one!!!!!!

The HQ Sweet 16 is a sweet machine.
Ask why they are selling it. ($2k is a lowball price). I've seen them for $3,800.
Ask what version the software is. If you want to ever use it with the TruStitch regulator, it needs to be at a certain revision.
Ask if it has the regular foot or the open toe foot.
Ask if it includes just the table or if there are extensions.
Ask if the bobbin winder is included and if it is the industrial-looking model of winder.
Ask how many bobbins and what extras (if any) are included.
It requires a special oil and special needles.

BTW, there is a YAHOO group dedicated to HQ Sweet 16 - you may want to join.

The required needles are type DPx5 also known as 135x5 or 135x7 or SY1955. I buy mine from Wawak.com for $2.10 per package of ten. Wawak also has great prices on quilting thread.
Standard sewing machine oil comes with machine and I've seen recommendations of a drop with every bobbin change to every new project.

Barring any mechanical issues with the machine, I would jump on this deal 'like a fly on stink'. Every owner I've seen post (here and on the HQ site) loves their Sweet 16's.

Don't worry about complicated accessories like zipper feet or button hole gadgets. The Sweet 16 doesn't have any of those. It's a single function machine for free motion quilting, and free motion ONLY. It doesn't even have feed dogs! If you know how to free motion quilt (even if you're a beginner) you already know how to use the machine. I've had one for about 2 months and love it.

I have had an HQ 16 for about 6-7 years now, and absolutely love it. I know the Sweet 16 is the bare bones machine, but not really sure what that is anymore. I have a stitch regulator on mine, and never quilt without it. My friend never uses her's, so I think it's really what you become a custom to. I never have tension issues that a few adjustments can't fix, and it runs any kind of thread I have put in it beautifully. (even metallics) HQ has great customer support which counts for a lot in my book. I would ask around to see if there is a repairman in your area. That would be my biggest concern with any machine purchase. Babylock now carries the Jewel, which is made by HQ, so if you have a Babylock dealer nearby, they should be able to repair and maintain it for you.

i have an HQ16 on the table as a sitdown, bought it used, still learning but it is fun! It can be a sit down or can go on a frame. I don't believe the sweet 16 came out till late 2010 or 2011- As my 16 was purchased in sept of 10 and the sweet hadn't come out yet.Really good price if the table comes with it I paid 2500 for whole package with some extras.

I purchased a used HQ from a Craigslisting. I went to the home and the owner had it set up and showed me how to use it. It came with the table, bobbins etc. She had it set up with a test quilting piece where she showed me and I tried it out. The owner was upgrading to a newer one. It was a positive experience and I have had a lot of fun with it. I am self taught through videos etc. I am a novice but through our sewing group I quilt our charity quilts which is great practice. You just have to be knowlegable about the product and who you purchase it from.