Value it the same you would a "real" product:

What is the replacement cost?:
If there's no comparable product - what would be a cost to hire someone to re-do it from scratch? What would be the cost of working around some IP/patent contained within?
If there is a comparable product - in what ways is your product better, in what ways is it worse - what is that difference worth?

The "sunk" cost - the time you've already spent and can not "un-spend" should be irrelevant to your decision.
Even future "costs" are not that relevant to the price/value - things can be worth more than what they cost to build(e.g. Mona Lisa is worth more than paint+frame+canvas+30% margin)

Value it the same you would a "real" product:

What is the replacement cost?:
If there's no comparable product - what would be a cost to hire someone to re-do it from scratch? What would be the cost of working around some IP/patent contained within?
If there is a comparable product - in what ways is your product better, in what ways is it worse - what is that difference worth?

The "sunk" cost - the time you've already spent and can not "un-spend" should be irrelevant to your decision.
Even future "costs" are not that relevant to the price/value - things can be worth more than what they cost to build(e.g. Mona Lisa is worth more than labor+paint+frame+canvas+30% margin)

Value it the same you would a "real" product:

What is the replacement cost?:
If there's no comparable product - what would be a cost to hire someone to re-do it from scratch? What would be the cost of working around some IP/patent contained within?
If there is a comparable product - in what ways is your product better, in what ways is it worse - what is that difference worth?

The "sunk" cost - the time you've already spent and can not "un-spend" should be irrelevant to your decision.
Even future "costs" are not that relevant to the price/value - things can be worth more than what they cost to build(e.g. Mona Lisa)

Value it the same you would a "real" product:

What is the replacement cost?:
If there's no comparable product - what would be a cost to hire someone to re-do it from scratch? What would be the cost of working around some IP/patent contained within?
If there is a comparable product - in what ways is your product better, in what ways is it worse - what is that difference worth?

The "sunk" cost - the time you've already spent and can not "un-spend" should be irrelevant to your decision.
Even future "costs" are not that relevant to the price/value - things can be worth more than what they cost to build(e.g. Mona Lisa is worth more than paint+frame+canvas+30% margin)