I do my company accounts on a spreadsheet. It’s pretty easy to set one up. Just pick some suitable columns. Category, company, description, money in, money out, date, extra info, etc.
Easy to add an extra line for each new item. At the end of the year you can total up the in and out columns and arrange everything by the category or date or whatever you need.
Might seem a bit daunting to set one up from scratch but it needn’t be too complicated. You can also tweak as you go and realise you need something slightly different.
You can also use an online spreadsheet so either of you can access it from anywhere and it’s all backed up.