Motobecane Mixte - Know Anything?

I am going to look at a Motobecane Mixte tonight and I was wondering if anyone knew any specifics about these bikes. The woman who is selling it does not know anything about it or bikes, and I asked what questions I could. From my brief internet research and from looking at the fuzzy Craigslist picture of the bike, it is 50cm (I ride a 49cm road bike), has friction shifters on the headtube (10 spd with Suntour components, it looks like 70s era bikes had this style shifter while newer ones had downtube shifters), diacompe brakes, it has riser bars (but it looks like most came with drops), I only saw lugged ones online but I cannot tell if this bike is lugged from the pictures (I would prefer a lugged frame). My specific questions are pretty much price related. What is a fair price for this bike? From how she described it I would put it at good to excellent condition. I am willing to put some money into it to get it where I want it (probably would upgrade to indexed bar-end shifters, I really struggle with the friction ones) and would probably sell/retire my commuter and replace it with this. Anything in particular to look out for? This is my first foray into the used bike world so I don't really know what pitfalls to avoid.

Thanks!

Edit: I should add that I am not really in a rush to buy anything (or so I keep reminding myself). I love mixtes and am looking for a really steller one that I would hang onto. Also, I am moving across the country next year and should really wait to buy something new until then. My plan is to sell my current bikes before the move since I'm not really as happy with them as I want to be. I would probably want to move the mixte if I find the perfect one. If you would pass on this bike and hold out for something better, I would consider that helpful information.

Mixtes seem to sell for very little compared to other bikes the same age and caliber.
If she wants more than $200 I'd say keep looking unless it is "like new"

I used to sell and work on 70s Motobecane mixtes. They all had lugged frames. Find out if this is the Nomad model or the Mirage model. The Mirage was a higher level bike - better frame, better components. I'd pass on it if it is a Nomad. The shifters are on the stem, not the head tube. You won't be able to get indexed shifting with this bike. It has a 5-speed freewheel that won't work with any indexing system. You could install Suntour bar end shifters without indexing - they are very nice. Check whether it has a cottered steel crankset or a cotterless alloy crankset - could be either depending on year of manufacture. I'd probably pass on it if the crankset is steel, unless you really want to invest time and money upgrading this bike. But parts will be hard to find because French threading is no longer in use, and cotter pins could be frozen and impossible to remove. Check the rims for trueness, dents, and flat spots. Check that the hubs are smooth and the rear axle isn't bent. The Suntour derailleurs should be good for many more years. Diacompe brakes were never my favorites because they always feel rather mushy, so squeeze them hard and make sure they stop adequately. If you can get some pictures of this bike, maybe I could tell you more.

I have one. My LBS built it up and like DebW said it was not easy to do. But it is a lovely bike

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