How to present a windows desktop application as SaaS (providing remote access to the program)?

Question

VMware

I have a desktop program written by me (I wrote it for a long time, in Delphi, it works under XP ), it is useful for a narrow circle of users. I would like not to distribute copies of it to users, but to provide access to it (make a subscription).
I'm thinking about how this can be implemented - while I'm looking in the direction of providing access to a cloud virtual machine. I don’t like this option because you have to create your own instance of a virtual machine for each user, and even if something needs to be changed in the program, it will be difficult to do it centrally.
Advise, maybe there is another direction, or optimization of what I said. Thank you.

Answer 1

Either make it as a web application - like google docs, for example, or sell licenses. In the case of licenses, they often do this now:
a license for a year
every year a new version is released;
if a user wants to upgrade to a new version, then he pays about 20-30% of the total cost of the license
. Either advertising inside the application is like 2GIS, and the application itself is free.