I have been following Indian startup ecosystem for few years now. I have built multiple products as well done services work till 2011. Till now I haven't raised outside money as almost all the products were never resource or operations intensive.
Nowadays, there is nothing wrong in raising outside funding as that is how you build big and fast businesses and considering how costly it is getting to even start a business let alone run it, it makes sense to do it to hedge your risk but still, ideally you want to bootstrap for as long as possible.
This will give you an understanding of the fundamentals of businesses and finances. You need to learn how to build things, how to manage people, how to find early customers, etc., before you really start contacting investors. Another thing is, by bootstrapping and being profitable, you will have much higher chances of being chased by investors and to get higher valuation.
They know because they did initial programming, user onboarding, marketing, selling and support, something which is very important. I strongly feel that even if you are not a great developer (I am also not a really good developer and often copy/paste code) learn and understand the technology stack as it will help you a lot to make the right decisions. Similarly, understanding sales and marketing is equally important. If you are bootstrapping, make sure the core team of co-founders do all this by themselves. It doesn’t matter how small and trivial the task is, do it once and then you can delegate to others.
Search for startup deals and offers in Google and you should be able to find plenty. Do search for coupons and discounts too as most of the SaaS companies do extend trials through coupons. I had also hired a freelancer from Philippines in 2013 for well below the market price and he helped me a lot in testing the product, so keep using freelancers too if you can get the work done fast and cheap.
With our current product AeroLeads, we keep looking for free marketing channels. For example, I did a podcast interview last week which has thus far got over 1200+ listeners. Though this may not be a big number, it still helps you build a brand and increase your product visibility.
Many startups also spend money on costly furniture, merchandise, etc. Again nothing wrong with that but you can do this later once you have some revenue.