I will try to simplify question.
I waited to call tax man today, after the rush, and I found out he left on vacation for two weeks. Please respond only if you are a tax professional:

Simple version
1st property = 200000
Downpayment = 40,000
crap load of expenses and tons of write offs = xxxx
Sales price 350000
Selling expenses 20000

Ending proceeds (money received) at end of sale = 140000
CPA said that my taxable gain is 100000

140000 went straight into the 1031 exchange.

Do I have to invest the full 140000 cash in exchange to avoid taxes?
If my taxable gain is 100000 (remember I put 40 down to start), then can I reinvest 100000 into a new property and take 40000 out of the exchange later and not pay tax on the 40000 since the 100000 invested matches the taxable gain. I know about the term "cash boot" but every site I see says I must pay taxes on the cash boot. If 100000 was invested, wouldn't it be extra?