Yoga props are critical to any home yoga practice, but there is no need to spend a lot of money to buy them. You can get the basics for under $50. The rest, you can build over time. As a start, I recommend a 1/4 inch Extra Thick Deluxe Yoga Mat by YogaAccessories. These mats cost about $20, and are extra thick and extra long to accommodate bodies of all shapes and sizes.
I also recommend purchasing at least two blocks, and one strap. These are my wallet-friendly favorites:
Once you have the basics taken care of, you can start to build on luxury items. Perhaps the single nicest thing you can do for yourself is to purchase a lavender-scented eye pillow. Seriously. I own three so that I can cover my eyes and also weight my hands in restorative poses. I recommend pillows with removable covers that you can throw in the washing machine. This guy is available for as little as $7.49.
One or two blankets are nice to have for support. If you have a Restorative Yoga practice, I recommend building a collection of six. I love these because they come in solid colors, but they are a bit pricey at $26-$39 each.
These traditional blankets are $16.49 each.
Bolsters are a splurge item, but it's worth buying a good quality one. If they are too bulky or have an awkward shape, they can feel difficult to maneuver. My favorite is this Hugger Mugger Standard Choice Bolster, which starts at $60.75. If you have a Restorative Practice, build up to a collection of two bolsters.
Please comment with any additional questions!