I don’t have much experience with bringing an existing business transactions into Manager. When I started Manager, I started with a new business so I started from scratch.
There are two ways to pay an invoice.
You can create a purchase invoice with the relevant details (my preferred method).
You can go to cash accounts and spend money and put in the name of the Supplier, Expense Account and other details there.
Technically if you pay the invoice immediately when you receive the invoice from the supplier you don’t need to create a purchase invoice as your are paying it immediately. A purchase invoice becomes necessary when you have received an invoice but you are not going to pay it immediately.
The reason why I like using Purchase Invoices even though most of the time I am paying it immediately is because it makes it much easier for me to view only purchase invoices such as when I am printing out all my suppliers invoices for a paper copy. A lot of payments in spend money are not invoice payments such as bank fees, salaries etc.
You should create a supplier for each company that you buy from. This will be very useful down the line to see how much you spend with each company and review if you can get a better price elsewhere and many other reasons.
I don’t use bank reconciliation as I manually check things, so I am not sure how this works. The reason why your invoices are appearing under the suspense account is because you have not allocated them to an expense account like inventory on hand if we are talking about your product purchases or delivery fees if we are talking about courier company charges.
Before you allocate everything to inventory on hand, decide if you want to use inventory on hand and sales of inventory as your two accounts to buy and sell inventory or if you want to break up your inventory purchases and inventory sales into categories such as Inventory Computer Purchases and Inventory Furniture Purchases if say for example you sell computer equipment and furniture equipment for the office. You might want to split the two types of inventory into two expense accounts and two sales accounts. If you look at inventory items you will custom income account and custom expense account. You will need to creat the income and expense accounts first in chart of accounts.
I suspect that you need to create quite a few income and expense accounts first in chart of accounts in settings as you may not have customised that yet.