I'm a one man band business owner, having run my web development business for 11+ years, 8 of which I used no project management tactics at all - other than code like hell and persistence. I also used contractors and employees for 8 years, but have sized back to myself over the past 3 years.
I've adopted risk management techniques - Project Survival Questionnaire as well as switched from fixed price to time and materials.
Currently I have 5 projects between 2 and 12 months behind schedule and I have identified that I need to complete them before accepting new clients. There is a 6 month old project which is for a client of 10 years that will sooner or later become impatient.
All my projects have scope creep, this was by design, as I endeavoured to service clients for as long as possible. However, now I want to move to a more structured approach, where I regularly review client relationships and terminate them if they are not aligned with my strategy. I want this process to be transparent to the client.
I'm looking for advice to get my timeline issues under control: How to temporarily stop scope creep, so the projects can be brought under control and completed. Naturally I would like to work on oldest first, but there are other constraints - cashflow from existing project stalls.