They aren’t friends worth having. Or family for that matter. They should be paying full price to support you.

Either just say no, or have a friends and family price that is x% discount and stick to it. This should be modest, like 10 or 15%.

Just answer the questions. How hard could it be?

You aren’t telling them why they should pay more. It’s not the product, it’s your marketing and promotion

Portable toilets. Good money in this but it’s shitty work

Provide a small annual return allowance. Maybe 10% and they have to buy the same value as the return.

Friends and family

You are assuming that is why people want a breakdown. It’s totally reasonable to want to know the cost of part versus labor for a job. You don’t need to break it down by part number so it’s easy for them to cross shop you. Just give list out the parts with a price by each item and then the labor costs.

Also explain that when they buy the wrong parts (which will happen 50% of the time) that you are charging for the call. Also explain that any warranty you provide is contingent on you supplying parts that you know and trust.

It’s a terrible idea unless you have experience running a coffee shop and know what you are doing.

Menu, suppliers, recipes for food and the thousand other details that you need to have a handle on will be overwhelming if you don’t have experience. Add $300k in debt to that equation and it’s a very tough path.

Hire someone to do the books. In my mind the platform is less important. I have used Xero and quite liked it.