Indoor/outdoor putting green?

go to home depot or loews and buy some astro turf ( basically fake grass ) it will cost you about 10 bucks then get some wood and make a raised bed ,,so you can have a hole to shoot for ....then you can change the wood and drape the turf over it to make more challenging up hill down hill type shots ,should be great to practice on .
good luck and have fun with it ~!