How to organize apps on a server

I am having a dilemma.

I am building a business where I have to provide an application which will help other businesses to manage records of their customers and I have 150 potential orders.

I have already built the application and couple of customers are already using it.

Technologies I used are - Node.js, AngularJS, MySql...

Next step was to put the app on a server, so I got basic VPS(1GB RAM, 1 CPU(2.2GHz)). There I have Debian with Nginx, and besides that, I got a domain.

I have two options how to manage apps on the server.

First one...

Every user would have their own app and database on the server. They would go to company1name.mydomain.com and Nginx would redirect the request to the Node.js running on specific port with configuration for "company1".

Second options...

I would have one app which would handle all customers.

The first option is by far easier to maintain, but the database will be messy and if something happens to the app everyone would not be able to access it.

Can someone tell me pros and cons of these two options, and advise me some other solutions?

I also would like to know what VPS hardware configuration would be good for handling 150 customers. There would be maybe 20 inserts and maybe 150 reads per customer per day, not much work.

Cheers!

via Miodrag Lazic