Creating your own painting studio inside your home is something that will serve you well if you're modelling competitively. However having the right lighting conditions, furniture and space will make all the difference to your levels of comfort and your ability to accurately paint intricate details. You'll also need to consider toxic fumes if you plan on using spray cans or an airbrush indoors, as well as the type of desk and chair you'll be using to minimise the risk of repetitive strain injuries and back pain.
Natural lighting will make painting much easier; however, at the same time, too much can hinder you as well. You should be able to manipulate your natural light source whilst having plenty of artificial light that can be moved around the model to light up areas of shadow. Using either indoor or outdoor blinds can help to change the intensity of the light outside, whilst extended desk lamps with moveable stands can work from both sides of the model to reduce shadows. If you are struggling to focus on the miniature as well, it may be because of visually distracting cutting mats or desk covers. Instead, paint your wall behind your desk white, and you'll be able to hold the miniature up against it to allow you to inspect the various tones of paint.
You may be working for long periods of time at a desk, which can easily lead to lower back pain and strain in the base of the neck. Try to invest in a sturdy desk chair with a lower back support, and the ability to be raised and lowered easily. If you couple this with a desk that can also be electronically raised or lowered, you'll be able to work comfortably for hours without injury.
Reducing Toxicity Levels
If you're going to be using toxic sprays or airbrushes in the room you'll need some way of removing the harmful chemicals. Opening the window isn't always the best option because the increase in moisture from outside can ruin things like varnishes. Instead buy an airbrush studio that can be placed onto your desk. These have built in motors and fume pipes that suck up harmful chemicals and paint, and release them outside. The end of the pipe often looks like a vacuum attachment, and will sit on the window ledge. This means you won't have to open it all the way.