If you don't have a tax consultant, get one; you can pay and deduct these expenses out of the business.

I do a monthly transfer from my business to personal checking within the same bank - it's free - takes less than a minute per month.

I dump my bank transactions as csv and drop them into a google sheet - this gets handed off to my tax consultant at the end of the year.

My tax consultant tells me when to pay payroll taxes -- either quarterly or I might just lump it into the last couple quarters of the year depending on how my situation for the year is shaping up. I login to eftps and edd and do this manually - again, doesn't take that long.

It's lightweight for one person - I never thought to use a service to manage it.