Startup Equity Distribution / Investor Equity

Thanks for taking time to read my post and sorry for the loaded questions -- please read patiently to help me. Here is the scenario:

Founder has the startup idea vetted 3.5 years ago -- but never funded. Recently the stalled venture is showing signs for attracting investors. There are two working partners who entered the scene just now. The venture has three phases. Phase 1 r&d. Phase 2 development and phase 3 tracking.

Questions:

1. Is it appropriate to call new working partners co-founders or founders? The venture has not been funded or started yet. The idea is the founders', the new working partners will get started only if funded. One of them is a peer techie, will be involved FULL TIME from phase 1 the other is marketing/sales development and will not get started until the end or mid of phase 2 and will work part-time 25% time investment. How much equity/ options to these 2 and the founder and the investor?
2. Investor equity: for an initial 500K investment, for the venture initial valuation of say X amount -- I do not know how much that is -- what % of equity to the investor?
3. What are the questions to ask a potential investor (there is not much choice for mission match etc. so I take the first investor in), when should I ask for a term sheet how do things roll from there? Can I trust an investor who wants me to work for their firm in some capacity without giving anything in writing or a term sheet?

Q: Is it appropriate to call new working partners ...

A: You can call them anything you want. I would agree with Alain that they are working pre-money, then they theoretically can be called founding members.

Q: How much equity / options for a) full time technical person and b) marketing person @ 25% time.

A: How to Divide Up Your Company's Equity - flavor to suit your condition.

Q: What % equity does 500K get?

A: Just like the show dragons den / shark tank, it is whatever you negotiate and they accept. Could be 20% - could be 70%. If you don't have a compelling offer, likely it will be zero.

Q: What are the questions to ask an investor? When do you ask for a term sheet?

A: You can ask all you want - but you won't get anywhere. Most of the time you are there to answer their questions - Investors expect you to be prepared. Term sheets are offered - not something you ask for. Suggest jumping over to venturehacks archive section and learn all you can.

In the future, if you break up the questions you'll likely get better answers. Best of luck.

1. Yes, they should be, officially, co-founders, but should not share an equal stake of the company than the person who founded/started it, if any significant work has already been done in the time from the conception of the idea. A good idea would also be to vest their share in the company.
2. Depends on your pre-money valuation. Also, product has to already be showing some signs of life or have a super-amazing team around it that investors would be willing to fund half a million seed round. If possible, start with something smaller with an angel from relevant industry that can help you grow to that next stage, so you don't give away a ton of your own equity straight away.
3. Don't take stupid money (from anyone that is willing to write a check). Find an investor that is knowledgeable about the industry and has a track record of investing in your type of companies. Check with companies he/she has previously invested in, especially the ones that went south or struggled, and see how they reacted in those situations.

For term sheets, read the Brad Feld term sheet series