Detailed description
A patch quote that looks cheap is usually a quote for a different attachment. Heat transfer, sew-on and adhesive backing are three different products built from the same artwork, and only one of them suits the garment in front of you.
Where it is used
It is used where the logo has to survive industrial laundering rather than a home wash. That is a different specification: a higher melt point on the adhesive, a tighter edge on the cut, and a backing that does not delaminate after forty cycles at 60 degrees.
The material question
The construction is made to artwork, so the material and the attachment method are agreed before tooling rather than described in a catalogue. Send the drawing and the fabric it goes on and the construction follows from those two facts.
How it is quoted
Artwork has to be vector, with the colours named rather than eyeballed, and the physical size stated. A raster file scaled up loses the edge, and a colour picked from a screen will not match the thread or the film on the day.
What ships with the goods
Certificates cover the base material rather than the artwork: REACH and RoHS declarations for the film, PVC or silicone, and OEKO-TEX documentation where the item sits against skin.
Checking it on arrival
Wash three pieces before you approve the bulk. One wash tells you whether the bond is right; three washes at the temperature the garment is actually laundered at tells you whether the edge will lift in service.
If this is a repeat order, send the previous artwork reference and we will quote against the tooling already on file.