I find your question extremely confusing. I suspect you could find a reddit group or another forum better suited to educating yourself. My suspicion is that this is the first time you have tried to run a business, and you are following the assumption that you need to raise money.
Disclaimer: I am just a random, with a bit of academic knowledge, and a little experience, but I will share my definitely naive thoughts with you.
YC SAFEs are uncapped, so I think they are irrelevant to your question. https://news.ycombinator.com/item?id=35382355
If you want $100k, then why are you not trying to get into YC? Build your MRR in the meantime. Spend no more than say 16 hours preparing - the YC process is supposed to be very light (and some successful teams do zero prep). On their end they spend 10 minutes reading your application, and 10 minutes if you get an interview. That’s it.
AFAIK a SAFE valuation is the valuation when the shares convert during an A round - after you have built the business. The point of a SAFE is so you don’t have to value the business now. So you present to investors where the business will be in say a year’s time after you have spent their money. If you or your investors don’t understand the instruments you are using, I think that is a very bad signal for you, the investors, and your business.
Note that a rule of thumb is that early investors aim for 30 times return on investment to cover their risks (most businesses fail, and zero return for many years). Also note that the video I linked talks about it being normal for founders to end up with 50% of a company when their Round A occurs - and that 50% is common shares so worth wayyy less than the preferential shares. Common shares suck. Minority shareholding sucks balls.
Did you watch the bootstrap video? Solid advice on how to bootstrap a business. Watch it again. Use annual prepay to get the business marketing engine running. Although I am guessing you are doing B2C at $10/month which is a hard road, and the video doesn’t help you much there (he just says don’t do B2C!).
Meanwhile you are being distracted trying to get investors for a fairly trivial amount for a developed country. We considered trying to get that in New Zealand when we first started ($100k for 10%) but decided it would waste time and bootstrapped instead - wayyyy better outcome. If your business is going to be successful, then concentrating on sales now is usually the right path (even if you do need money later). I love the repetition here: https://medium.com/how-to-start-a-startup/47-quotes-from-sam... - you could read that every day and it would still not hammer home how important their message is - we are deaf to great advice, and too many of our beliefs are based on fictions.
Learning about investing is a huge time sink. The YC model is they aim to be co-operative with founders, so founders risks are lessened, and the deal is great (so it is fairly no-brained to take the deal now and learn the details later, assuming your business matches YC’s model). Other investors tend to be more mercenary - watch out. When our company was in an incubator, it was sad watching other companies chase investment, and get distracted by investors, and the process. Investors might mean well, but their advice or pressures are all-too-often extremely counter-productive (especially so in investment naive countries like mine). Paul Graham talks about the distraction here: http://paulgraham.com/ramenprofitable.html and here: http://paulgraham.com/die.html and about why VCs suck here: http://paulgraham.com/venturecapital.html
Any reading you do should be hyper-focused on helping build your sales. If you are looking at anything to do with understanding funding, VC, SAFE’s, preferential shares, then you are highly likely to be distracted. You are not trying to get a degree - avoid learning potentially “useful” stuff for the sake of learning.
Most of the above is academic, from spending too much time reading and not enough time doing. All of the above is situation dependent: make your own decisions based on your own needs. And beware of all advice - 50% of the best of advice will still be wrong or wrong for you. To quote Jim Keller talking about himself: "Imagine 99% of your thought process is protecting your self-conception, and 98% of that is wrong.” — context @1:23:00 of https://www.youtube.com/watch?v=Nb2tebYAaOA
Please reply, so I can tell how much of your time or my time we have wasted!
Good luck.