I really don't understand why I am stuck to using the calculators only 5 times per account. I know that it is an incentive to buy the Pro plan, but I am not in the position to spend for the pro plan. Especially when I am brand new to REI and I am no where near ready to make a deal. But I need to practice crunching numbers and seeing the big picture so I can find good deals
Are there other free substitutes to BP's calculators? And I mean free, not "you tried it free for 3 seconds, now here is a pay wall"
Yes the best way to do this is to create your own calculator. Doing so will probably teach you more about the process as well, it is a fairly simple thing to do in Microsoft Excel or Google Sheets. It shouldn't take more than an hour or two at the most.