Tenancy In Common agreement - can percentage splits be fluid?

[Mel Cosio]

TIC agreement question for the experts on this board:

A normal TIC agreement would specify the fixed percentages of each partner. For example, if the TIC is buying a 500k house and my company puts in 250k, my percentage is 50%, partner A puts in 250k so her percentage is also 50%. When future expenses come up (taxes, utilities, etc), I cut a check for 50% of the bill and my partner cuts a check for 50% of the bill.

So my question: if my partner only wants to contribute 250k and no more, can a TIC agreement be structured in such a way that percentages will change as expenses occur? For example, if we get a 50k bill, and my company pays the whole 50k, that would increase my contribution to a total of 300k, which will make my percentage 54.5%, and partners percentage to 45.5%. if another 50k expense comes in and my company pays it, my contribution will now be a total of 350k, my percentage will go to 58.33%. So when we sell, my keep will be 58.33%, and the rest to my partner.

Is this TIC arrangement possible / doable?