Any machine that has straight and zigzag will do.

Check Craigslist for an old Singer 235

A Singer 301 is a featherweight's "big sister", and if watching yard sales or craigslist, can be bought for under $100 dollars. Also a Singer 503 is good, sturdy one that has zig zag. Newer machines are truly more trouble than they are worth. Go with an older one and you'll be happy to help her.

Try to find a Swedish made Viking Husquevarna home model 6970 (or There about) from the early 80,s they last forever.

It depends what you define as inexpensive. I recommend a Janome HD3000. It is heavy duty enough for making pillow cases and heavy curtains and will hem blue jeans. It works just like your Singer (for that matter most sewing machines do) and has a few more stiches should she want to expand her sewing repertoire. It costs around $400 new. Of course you can also buy Brothers and Singes for around $100 that may be a good place to start to see if she will stick with it. The challenge is there are a mind boggling amount of sewing machines to choose from. What ever she decides to get I recommend she get her sewing machine from an authorized dealer that services the machines they sell. They will typically offer classes, will get her set up, be there to answer her questions and to service the machine should she need it. Good luck!

When my wife's Singer featherweight needed service, I decided to replace it rather than have it fixed. I just went on ebay and looked for Viking sewing machines. There were tons of them. I found a second hand Viking Husquevarna model 400 computerized one for about $159. It is so much more than the ones you can buy new for anywhere near that price that I ordered it. It came in perfect condition. I have used it to stich a variety of stiches but not for embroidery.

I have owned a Husqvarna 500 since 91 and it finally bite the dust. The repairman told me how much it would cost to repair it and it was outrageous. I looked om Ebay and found the identical machine but it sold for more than I cared to pay. I found another one about a week later and I bought it for less than the repairs would have cost on my older one. It came in pristine condition looking as though it had never been used. I have had it for about a year now and have had no problems at all. Since I already had one like it I never went through that phase of learning how to operate it. I LOVE my Husky. I also bought a used Husky that is about 20 years old that was only $15.00. Keep your eyes out in thrift stores for bargains.

My Viking was the most used Viking home model ever owned. I did a lot of production sewing on it and it was the only one my servicer/ Viking dealer had ever seen that needed a new motor. Luckily for me he put that in even though the 10 year warranty had just passed. It was the second from the top of the line at the time ( which was computerized, so I did not care for that) and cost 800 bucks brand new in 1980. It still works better than the one I bought recently, same model, on CL. ( for 120) Keep in mind that a machine that sits around and does not get to sew is an unhappy machine.

I agree Juboka. That's why whenever I see a lonely forlorn looking machine in a thrift store it ends up following me home. For the most part almost all of these machines just need a little clean-up, or oil or a few minor adjustments.