Calculate Total Costs based on Recurring Costs, Start Date, and Frequency

Hi, hoping someone can give me some guidance.

I have a list of costs that occur at different frequencies (one-time, monthly, quarterly, daily, etc.), based on the start date of each cost I need to calculate the total (since that start date) and the projected total for 2021.

For example, if I have Cost A listed as $10 monthly and started Jan 1, I would need formulas that calculated the total cost since cost began $20, and the total projected for 2021, $120. 1 more dimension. I do have another column that lists the status of these costs. For the costs listed as "In-Process" or "Planning" I need the total since costs began to equal 0. Probably much easier to understand via the attached sample sheet.

I know I can get there with nested IF(AND statements and helper columns that calculate # of occurrences since start date and total # of occurrences in 2021 but, what would the easiest way be? I'm trying to avoid helper columns if possible.

Any help would be much appreciated.
Thank you!

Thanks for the reply.

It's not fiscal quarters, we just have a couple of costs the occur 4 times in a calendar year, they are pretty much seasonal so I'm not defining with specific dates. I'm taking the month and dividing it by 3, December would be 12/3=4, then subtracting that from 5, and rounding up. So a quarterly cost that occurred for the first time in December would only happen once in 2021, (5-(MONTH#/3))=1. For bi-monthly, I'm referring to costs that occur every 2 weeks, 27 total for 2021. I'm using the same process but with the week number.

I'm probably making this needlessly convoluted so if there is a simpler way I'd love the input.

I was also thinking I could calculate the quarterly and bi-monthly costs into their monthly amounts (bi-monthly times 2 and quarterly divided by 4) in a helper column and go from there with the monthly costs. But I'm trying to limit the number of helper columns/potential areas where the multiple users could potentially edit things they aren't supposed to. That's a different issue though haha.

I appreciate the help, your way does seem to be the simplest I have attempted and I can handle cost 5. I actually think helper columns are super useful. But in a recently shared spreadsheet a co-worker, in an attempt to be helpful, deleted "all those hidden columns we weren't using". The way our system works locking shared docs is difficult and you can't lock a document if someone has a certain level of access. Which is silly because it's not like the CEO wants to change your formulas but there it is.

You have given me an idea though, regarding the "aesthetics" I'm sure there is a way to hide those columns so well they can't be found to be deleted. Hidden columns on a hidden worksheet, named "Do Not Touch"?

Thanks again this is just the direction I needed, plus you've given me a great idea to play around with.