I use Google sheets on my personal projects.

• tracking expenses
• tracking my ride logs from my ev

Google app script pickup email received from banks and update the transaction automatically. I modify it using web based form of needed.

The ev company has api. It will be called on periodic basis to get the ride details and update the sheets. I use telegram api to interact, by triggering the api webhook, getting charts, etc.,

Initially I setup OCR to extract the ride information, so the process was like

• send an image that has ride details to a telegram bot
• the bot saves the image in Google drive
• the image would be opened in docs
• the text would get extracted and stored in Google sheets as data
• edits can be done using telegram webapp
• sheets provide charts for analysis
• built a process using sheets to handle telegram bot for maintaining users, approvals, etc.,

It would be hard if I have used any other services… setting up OCR preparing charts etc.,

Try to add 100+ things to make it very big project, then dropped without even completing 10% of to-do list.

Eventually you get a better idea to start the same project from scratch, then drop it.

Wireguard + pihole?

What I feel is that you need do is to compare the cost of power supply vs hardware then choose whichever is cheaper.

A good read about self hosted email servers: https://news.ycombinator.com/item?id=32715437

If you are going to use it within your family members it will be fine, but not with other users who uses corporate provided email services.