Would one of you mind explaining how finding seller financed deals would benefit me or otherwise enable me to acquire property faster?

IHMO, you are enabling your tenants to take advantage of you by allowing them free, unchecked & unfettered use of services that (only) they use. 

This will include, but not be limited to the transaction not being closed because Seller is unable to complete the transaction for a qualified Buyer, or because the property does not appraise for an amount sufficient to enable the lender to make the required loan, or because Seller elects not to pay for the excess amount in paragraphs 4 (with respect to repairs), 9, or 11, or because the zoning is not as required in paragraph 16 or because Seller cannot deliver marketable title.6.

That surprised me because I thought the whole purpose of the contingencies is to enable one to back out.Is there any issue with making more offers than you can finance at once if you have contingencies to back out?

Please contact your system administrator to enable the account." and not letting people sign in.

If they want to purchase the lead, you could fulfill it via a Square-enabled online store: https://squareup.com/sell-onlineYou could also do a similar thing with Infusionsoft, but it's pretty expensive (~$300/month).

It then enables him to move down a little bit.I think the large firms churn out so many bids and just wait for the phone call which will accept their bid.

I’ve seen articles and heard podcast that suggest this would give me an equitable interest in the property and enable me to legally market it (without a real estate license) and then do a double close2) Secure a special power of attorney from the owner granting me the authority act on their behalf to market the property for a defined period of time and receive a portion of the profit from any sale at closing.Any thoughts on either of these approaches or any other approaches that would might be legal / illegal, particularly in Texas?

I love making money and dislike spending money, so I'm entertaining an idea that may or may not be viable, but I wanted to get opinions/advice before proceeding any further.Because I do not have a family or many personal possessions, I thought it could be a win-win if I lived in a property that is being rehabbed by an investor.The pros and cons for me as a young professional interested in investing are pretty obvious: I live (potentially) rent-free, enabling me to save more money to invest.

And you enabled them by not enforcing the terms of the rental agreement.