Should I spend time talking to 100+ potential customers before building, or just consult the handful I already work with?

Find apps that are B2B and go to the review sections. Specifically going to Google's play or Chrome store and look at reviews and follow them to Google+ to engage. I took that same angle for B2C app I was building last year. Check it out. http://blendah.com/post/37331434653/lean-startup-hack

It varies and it's very very specific to what you want to develop. The concrete design of your circuit matters. Also prototype building costs are usually a factor 10-100 higher than series. If you already have your prototype then you can shop around various manufacturing companies. To do that, you need Gerber files (your PCB design) and a bill of materials. You also need to think about casing: designing it and creating the mold is expensive. If you don't have your prototype yet, I recommend having it engineered in eastern Europe. Custom engineering is cheap there and high quality. IP protection is a problem. One thing to do is to distribute the work to different manufacturers. For the design phase you are safer if you design your prototype in Europe or the US where international patent laws apply. I could give you more specific advise in a phone call, getting to know a bit better what you are trying to build.

Wow, lots of questions here. Let me try to hit them in order: "Should I get a job or find investors?" IF you have access to enough investor capital (not debt and not your savings) and you can get to MVP and still maintain ownership of a sizable majority of the business then do it. IF that means debt financing then only use the debt lines the cost of which can be carried by returns generated by the use of funds. I would prefer to offer a convertible note to prospective investors that can be easily extended throughout both friends and family and seed rounds (up to $2M to $3M) to get to proof in the market. If you can get to revenue and earnings fast enough then you can avoid equity dilution all together. IF you cannot secure that find of funding AND you cannot produce enough revenue from your business to deliver sufficient earnings for you to live on, then by all means, you should find a way to make the money you need and not burn all your savings or mortgage your home If that means short term contract work that's great. Particularly if you can find log term work that is relevant to the business you're building. If that means taking a job then do that. IF you do that, then yes, be transparent with your employer and let them know you're working on your own business also. Hope this helps....

You can only solve a big problem that changes the world if you solve a problem that is deeply personal to you. Two great examples and why they worked: Roy Raymond was a sad pervert. He'd buy bras and panties at the department store and all the clerks thought their thoughts about him. Roy felt embarrassed. He wasn't really a pervert. He just wanted to buy lingerie for his girlfriend. So he solved this major problem he was having. He created a space where men could feel comfortable coming in and buying sexy lingerie for their partners. He called it Victoria's Secret. But Roy, by solving this important personal issue for himself, apparently solved the same issue for many other men. First year sales were over $500,000 and he quickly opened up three more stores. In 1982 he sold Victoria's Secret for one million dollars before trying multiple other businesses that ended up failing. One MILLION Dollars. A decade later Victoria's Secret was worth over a billion dollars but Roy Raymund was nearly bankrupt and had missed the huge run-up in it's value. -- Picture New York City in the late 1800s on a rainy day. It was disgusting beyond belief. 150,000 horses transported people up and down the busy streets. Each of those horses, according to Super Freakonomics, dropped down about 15-30 pounds of manure. That's up to 4.5 million pounds of manure A DAY on the streets of NYC. And now imagine it raining. Would you cross the street? How long could this last? How long would the city survive without being infested with crap and all the diseases brought with it. What would happen as population of both men and horses increased? Was someone working on inventing a gigantic manure scooper? How would this problem get solved? It never got solved. Instead, Henry Ford invented the assembly line to mass produce cars. Every horse lost their job. People began to drive cars. Manure problem solved. -- In both cases there is a common theme. Someone outside the industry solved a problem that was personal to them that then changed an industry forever. Roy Raymund wasn't a fashion designer or a retailer. He worked in the marketing department of Vicks, which makes over the counter medications. Henry Ford, I don't think, ever worked in the manure industry. Instead, each person focused on a problem that was important to them. A problem that excited them at that moment in time. Raymund wanted to avoid being embarrassed in the future. Ford wanted an efficient way to make cars. The ONLY way to change the world is to solve a problem that is important to YOU. They had to choose themselves for success before they could save the world. Raymund had to convince himself that he didn't belong in the marketing department of a division of Procter & Gamble. He borrowed $80,000 and took the big risk of starting a business. Ford had to survive numerous failures and bankruptcies in order to find a cheap way to make cars. He would abandon investors, people who supported him, and even companies named after him, in his quest to solve his problem in his own way. Nobody gave them permission. And neither of them set out to change the world. They only wanted to solve a problem that was personally important to them. It's unfortunate that often we forget that choosing ourselves is not something that happens once. It has to happen every single day. Else we lose track of that core inside of us that solves problems and is able to share them in a way that makes the world a better place. Ford forgot this and became obsessed with Jews. Ford is the only American that Hitler mentions in Mein Kampf: "only a single great man, Ford, [who], to [the Jews'] fury, still maintains full independence...[from] the controlling masters of the producers in a nation of one hundred and twenty millions." And what happened to our embarrassed marketing manager that has ignited the passions of men and women for the past 30 years? Roy Raymund saw the value of Victoria's Secret jump from the one million he sold it for in 1982 to over a billion dollars a decade later. He failed in business after business. He got divorced. Then at the age of 46, my age, he drove to Golden Gate Bridge, jumped off it and killed himself. Before you can save the world you have to save yourself. But you have to relentlessly do it every day. Sometimes the train wakes me up at night and I feel scared. What will the world be like for my children? I won't always be able to help them. I don't even know if I do enough to help them now. And then I remember. I'm alive for another day.

The idea of an MVP is 'minimum, viable' ... If you feel you need a "good amount" of funding, I would challenge if you are minimum enough. Obviously, without knowing the details of your product, your ideal customer, or what need you will solve, it is hard to help expose what is necessary in an MVP and what is a Phase II or Phase III feature. I am happy to help you work through this, or answer specific questions, to get you rolling. Just book a call with some times that will work for you. Regardless, I would love to know more about it and how it goes after launch. To your success, -Shaun