Regrettably, your stated description of as “...having only slight almost invisible blemishes...” conflicts with buyer complaint of “marks on the underside.”
my take ....
(1) Buyer has a point that seller’s description was materially incomplete on the listing without prejudice to any value judgement about buyer’s regret or pickiness. Better supporting pictures in the ad and a better narrative highlighting its pre-owned condition marks in full as to its pre-owned condition is de riguere here.
(2) E-Bay has no published standards for audio equipment condition grading . Audio forums are a different animal that most invoke a published standard of sorts . On AGON or CAM feedback is arguably the first item buyers and sellers review before sticking their toes into the water. EBay feedback is worth something but again it’s not playing in a “pickier” audio enthusiast arena IMO.
Here is CANUCKAUDIOMART’s grading scale that sellers and buyers must read and follow:
Canuck Audio Mart Grading Scale
Canuck Audio Mart (CAM) uses the Grading Scale standardised by AudioGon (known as the AGS). Even if you are familiar with that Grading Scale, please read this through carefully, especially if you are claiming your item to be New, Mint, or Excellent. It is very important that all users use the same Grading Scale, so please follow this scale carefully. The condition of an item you list on Canuck Audio Mart should be identical to what you would list it as on any other site using the AGS. We have reproduced the scale here for your convenience, and it is directly from the official AGS.
For Grading Scales on Software Records, please click here.
11/10: New: Unopened Factory shipment
When an item’s condition is called "NEW", it must be a factory sealed box, and the seller should declare what if any warranty will be provided by the manufacturer. Some manufacturers will honor warranties only if purchased from an "authorized" dealer. Other manufacturers may offer warranty to the original owner only, even if that original owner never opened the box. Thus, any item rated as NEW should be accompanied by a warranty statement within the description of the listing. Otherwise, prospective buyers should ask the seller about the warranty - do not make any assumptions other than a factory sealed box.
If an item has been opened for inspection or any other reason, it should NOT be rated "New".
10/10: Mint - Essentially never used, factory fresh appearance!
The word "mint" is used so often that it’s meaning is taken for granted. In the Audiogon Grading Scale, Mint can be used to describe an item if it meets the following criteria without exception.
The item must have been removed from its’ original packing and and must be no more than one year old since opening or first usage and must be no more than five years old from the date of manufacture. The one year or less since first usage is a must - subtle environmental contact such as finger skin oils, household chemicals, smoke, and other airborne pollutants can negatively impact equipment. The result of this kind of exposure is a discoloration of the equipment’s surfaces.
- Electronics must have no visible scratches, nicks, or blemishes anywhere on the piece. The gold plating on input/output connectors should evidence no scratches or discoloration. Chrome should have absolutely no pitting or discoloration, especially around screwheads.
- Speaker grilles should have absolutely no pulls or discoloration. The bottoms of speakers should not show signs of stand mounting or floor scrapes.
- Turntables must not show any use, and their covers must have been left in the box - that’s how new they must look.
Very few pre-owned or demo items qualify for this level, so we strongly recommend a thorough inspection of the item before rating it a 10/10.
9/10: Excellent - Perfect physical condition, light use.
The item should be a one-owner or store-demo piece to qualify for a 9/10, though some exceptions will exist. The item should appear as new unless a very close inspection is performed, as described below.
- Electronics should look factory fresh except for dust in crevices. The plating on i/o connectors may show some use, but no discoloration or oxidation. The item should never have been rack mounted. Chrome should have no pitting and no discoloration.
- Speakers should be perfect except for the back or bottom, which may show slight indentations from stand mounting, but the indentations do not show through the veneer. Wood finishes should not show any change in color from sunlight, especially uneven discoloration. Grill cloth should have no pulls, but maybe dusty.
- Turntables may show slight wear where the cover is lifted, but no visible wear on the top of the cover, or the plinth. The headshell should have no scratches from cartridge mounting.
8/10: Very Good - Perfect front face, 1 minor flaw on top or side is acceptable.
This item has seen some use, but still appears perfect from the front. A perfect front face plate includes the front top edge. Be sure and check this edge since it is very easy to nick. On speakers, all four front edges should be inspected.
- Electronics may have 1 or 2 minor scratches (max 1/2" long, very thin) on the top plate or the sides of electronics, but again, the front must be perfect. There should be no signs of rack mounting. Chrome should have no pitting, but may have some discoloration in spots less than 1/4" diameter. Silk-screening has no separations, and the lettering shows no wear.
- Speakers may have minor discoloration along edges, but no scratches that show through the veneer, except for the bottom, which may show signs of stand mounting or floor scraping.
- Turntables covers may be slightly hazy from record sleeves being laid on them, but should not have any highly visible scratches anywhere. The headshell may have some scratches from cartridge mounting.
7/10: Good - 1 or 2 minor scratches, looks used but well maintained.
- Electronics should have no dents or bulges, but a few minor scratches. Perhaps a little wear on the knobs and switches, like the slightly darker or shiny coloration seen on volume knobs. If the item was rack mounted, plastic washers should have been used. Chrome may show slight pitting, but not enough to be visible without close inspection. Silk-screening on the glass is separating in at most one area of less than 1/2" diameter, and some parts of some letters may have worn off.
- Speakers may have loose fitting covers, or the cloth may have 3-5 minor pulls or 1 small hole less than 1/2" long. The cabinet may have one minor scratch that shows through the veneer, but no bigger than 1" long. The bottoms of speakers may show many small scratches or scrapes
- Turntable covers may be hazy, and the tonearm may show heavy scratches from repeated cartridge replacement.
6/10: Fair - 3 to 4 minor scratches, or 1 major scratch, appears used.
- Electronics may have one major scratch (over 2" long, deep enough to show metal) or a slight dent on one of the surfaces. The item must NOT have any major scratches on the front facia, but may have some nicks along the top front edge. Chrome may show obvious pitting, but should not have any flakes. Transformer covers may have some scratches, but cannot show any rust. Silk-screening is separating from the glass in more than one area, and some lettering is worn off, but the glass must have no cracks or chips.
- Speakers may have one major scratch that shows through the veneer, but no longer than 2", and no deeper than 1/16". Grill covers may have to be replaced to look fresh.
- Turntables may have scratch but not cracked dust covers, or pitting in the platter surface.
5/10: Average - Multiple scratches, including some on the front face.
This piece is visibly scratched and noticeably used, any major scratches on the front face qualify for a 5/10.
- Electronics may have several minor nicks or one major scratch on the front. Chrome is showing some pitting, maybe a flake or two has come off. Transformer covers show some rust, as do their mounting screws. Silcreening is separating from the glass in two or more areas, or the glass has one minor crack less than 1/2" long.
- Speakers may have 2 major scratches, or more than 5 minor scratches, grill covers may not stay on the speaker any more.
- Turntables may have cracked covers, headshell may have multiple scratches, and tonearms may have broken resting clip.
4/10: Mediocre - Rough physical condition, but all functions work perfectly.
This piece would not go in your "big rig", but is not worn out.
- Electronics may have many small scratches, or have a broken display face, or have a bent lever. Chrome shows severe pitting, transformer covers are very rusty, glass has one or more cracks in it.
- Speakers may have a dented corner or bent binding posts, but drivers are not physically disfigured.
- Turntables may have missing covers, or show much discoloration on the platter, or scratches on the plinth from the platter rubbing against it.
3/10: Poor - Rather beat up, but all functions work, maybe a knob is missing.
This piece now resides in the garage.
- Electronics have chrome that is pitted to the point of looking like a speckle finish, transformer covers are dented and rusty, and binding posts are very oxidized.
- Speakers have major scratches or chunks gouged out, but all drivers are unmolested.
- Turntables work, but one wouldn’t think so by looking at them.
2/10: Very Poor - Beat up, bent knobs or switch levers, some functional problems
- Electronics have major dents, knobs are missing, but they sort of work.
- Speakers have torn drivers or crinkled tweeters, or more than 3 major scratches, and grill covers have disintegrated.
- Turntables have warped platters, or tonearm bearings are too tight or wobbly.
1/10: Shot - For parts use only.
My take : selling audio equipment on Ebay is a risky poker shoot at best to a wider audience, but it’s not tailored to audiophiles .... stay on AGON OR CAM ...full stop.