Personally, I think bootstrapping, taking no outside investment at all is also a completely reasonable model (and often ends up with a more sustainable business, and can be executed by people that lack the sales skills to get investment)
If you are bootstrapping? 18 months is not a reasonable period of time to get something to the point where you can get group coverage. (In most states, to get group coverage, you need at least two employees on that insurance.)
also, I think it's quite valid to support yourself doing contract work. same problem; if you don't want a body shop to take half your pay, well, you need two employees before you can get group coverage.