You should move the thread (using the "Edit" link) to General Discussions (the Release section is from actually released fonts).
Anyway, a related thread discussing some of your questions:
http://typophile.com/node/30845

And split this monster up into parts!
You'll get better participation from people with different interests/expertise.

hhp

What are the must have characters/glyphs before releasing a font on the market?

For language support look at the large encodings of successful vendors like Vllg, H&FJ, etc. Display fonts can sell well with a smaller character set, for example, you can cash in on American design trends and sell well with a stripped-down Latin-1 font. Unless you are being paid to address them it is safe to ignore things like old Irish orthography, Esperanto, and Klingon.

What's the market looking for when buying fonts?

That depends entirely on the design of the font. Publication designers, package designers, and sign shops buy entirely different stuff.

Thoughts on font scalability? What is the lowest size do you test your typefaces out on.

This is determined by the style, weight, and purpose of the font. A font optimized for text gets tested at text sizes. A hairline sans serif has to be tested at large sizes because even a 2400 DPI laser printer can’t render it correctly below 18 points, and that’s if you have a $30,000 color Xante and the humidity is just right.

Is there much profit to be made in selling at foundries?

Sure. Especially if you don’t have the inclination to set up a business, create an online store, etc. etc.. You can do pretty well selling through vendors like Fontspring and Font Bros. that pay a bigger royalty if you can promote yourself.

Any tips/advice would be greatly appreciated.

Most people in the font industry are friendly, trustworthy, and not the least bit interested in screwing anybody over. That said:
- Read a contract repeatedly before signing it. Talk to a lawyer if you don’t understand any of it.
- Don’t sign a deal for a royalty rate below 50%.
- Don’t sign a deal that allows the vendor to deduct any business costs, including marketing, from your royalties.
- Only sign an exclusivity agreement if the vendor is doing a lot of finishing and production work that you would never get done yourself. Or if the vendor is willing to commit a lot of money to marketing your font.
- Don’t sign any contract that never expires. You have no way of knowing what a vendor will be doing in five years, or who might own the vendor.
- Never sign away ownership of your copyrights or trademarks.

Dunwich Type
- Don’t sign a deal for a royalty rate below 50%.

What about OEM licenses. Most vendors offer a lot less than 50% in these contracts.

What about OEM licenses. Most vendors offer a lot less than 50% in these contracts.

Good point, OEM licenses are a stickler. I don’t sell enough OEM licenses to offer advice there.

Is there much profit to be made in selling at foundries?

No.

so don’t bother with the other questions.

What about OEM licenses. Most vendors offer a lot less than 50% in these contracts.

I laugh at the 22 cent royalties I get from my old ITC fonts when they get bundled with some OEM package.

Mr Puckett offers good advice, but if it is your one and only font, your not going to do very well anyway. At least money wise. There may be a lot of people telling you how great it is, but they rarely buy anything

Although I do sell fonts directly, my experience with
Linotype and FontFont has nonetheless been wonderful.
The low royalties are handily offset by what they do with
the fonts before and after release. They're not crooks.

hhp

So Andreas, going your own is the only option?

What's the difference between an OEM license and a 'normal' license, whatever that may be?

What's the difference between an OEM license and a 'normal' license, whatever that may be?

An OEM license is a license for a software maker to include the font in software packages. These licenses are quite expensive. The big foundries claim that they do a lot of negotiating for these licenses and so royalties on OEM sales are in the 20 – 30% range. This is one of the biggest drawbacks to selling through foundries, and it’s not a bad idea to just not allow foundries to sell OEM licenses so that you can keep all of the money.