So I think most of us are asking what is the value of PPT when measured by traditional means. I'm going to take a stab. I appreciate comments on my ramblings and rough math:
For example, if you can buy a share/token for $1 and earn 3% per year, what will an investor pay for that stock plus $.03 annual earnings? 10x earnings is probably not unreasonable, so probably about $.30 give or take.
We'll ignore a supply/demand imbalance in the auction which would presumably also affect the interest rate and assume we can earn 2% monthly interest (24% annual interest)reliably. Let's also assume that you can use 80% of the current PPT market value to buy an invoice. For example, an $8k invoice would require $10k of PPT.
PPT is about $46 at the moment. 24% of 80% of $46 is $8.80.
Using a Dividend Discount Model with a Discount Rate of 2%, the calculated value per "share" is $440.
The interesting thing is that as the value of the token increases, the value of the earnings increase at the same rate. So a $440 PPT token would supposedly yield $88 annually. This then yields a token dividend valuation of $4408. So there is no limit to what PPT is worth except the actual ability to actually earn 2%.
The ability to earn 2% monthly interest depends on the supply of invoices and auction conditions achieving a consistent 2% monthly interest rate.
Not enough invoices, lower interest rate results in lower returns. Too many invoices results in higher returns.
The DDM doesn't take into account additional value due to anticipated increase in token price.
There are 37M tokens, so to achieve a $1000 token price, each token needs to be able to earn $19.20 interest annually. This requires a supply of $3.7B of invoices available that you can earn 2% monthly on.
That isn't to say that the DDM is accurate of valid, just one attempt at valuing PPT. Once people are able to see what real returns look like, and if they are close to these assumptions then $1000+ is no problem.
I think you're on the right track, but I see it a little differently. Because the amount you earn increases with price of the token, you can't really use a DDM approach. As you said, the constraining factor is the volume of available invoices.
So the market cap of the tokens should be approximate to the volume of invoices available. It'll be interesting to see what happens if there aren't enough invoices available, but my guess is that it'll result in some sell pressure so the token market cap doesn't ever go significantly above the invoice volume. There are some other factors at play, but that's the primary driver in my opinion.
That leads to the question of how much of the factoring market can they capture, as well as how much larger will the market grow now that more small businesses will have access to this type of financing.
I published a valuation model in the Telegram group that allows you to play with various assumptions, but that's the approach I used. I can see it going as high as $684 by the end of 2019 under the right circumstances.
Please keep in mind that this is not investment advice, so please do your own due diligence.