I'm debating renting one and there's a number of websites that you can pick from, ranging in price from $14 a month to over $60+. Ideally I want to keep it under $20 a month, and I'm not opposed to the six month bundle for the cheaper pricing, either.

 

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I used one my dad made when he first came to Canada... It was just a circuit board and doppler probe to put on your belly. Worked 100% fine. More bells & whistles will not change what you're getting. Either way you squirt on the gel, move it around a bit, and eventually find that oh-so-fantastic heartbeat you're looking for! Sometimes it's hard to pinpoint it, the baby's moving too much, or positioned just out of the way, but it's damn cool to listen too whenever you feel like it!

I'd go with the low end of the range of options, if it were me.

 

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