Changing cost of a unit through triggers

Is there any possible way (without jass :D) of changing the cost of a tower?

Im making a td where all towers cost more if you build alot of the same, for example if you build 2 watch towers a watch tower will cost 12 (10 + 1 for each tower built). I just dont want ppl to mass one tower, so i came up with this idea=)

or, if thats impossible:

is there any way of checking how much a tower cost through triggers?

Could you try upgrades to increase/descrese the cost? Have an invisable unit train them. If I get this to work, could I possibly suggest this fo rthe TD im on the team for?

Ahh thanks=) Well, if you could explain more exact what upgrade and such, that would be very helpfull... and of course you can use your own things in your own tds :D

Ahh thanks=) Well, if you could explain more exact what upgrade and such, that would be very helpfull... and of course you can use your own things in your own tds :D. but i cud use credit for the idea of that:) i like cred emote_sweat

Well i actually HAVE made one of these systems my self, when i first encountered this problem. I made so when you build the unit, it removes"the amount of structures of that type" from the owner of the building units gold. And then fixed so if the player doesnt have that gold, the building is removed. The problem is i want so when cost actually increase so you can see it in the unit descriton... possible?

And yes, u can use that idea for it.... but if you want you CAN give cred :D