1031 exchange refresher

[Nancy Bachety]

Using Round numbers 

Selling condo without realtor for $444,000 bought it at $144,000, $44,000 improvements, no mortgage, lived in first 5 years, rental for last 29 years.

1) In order to have zero tax liability on gains, is the minimum purchase price of new investment property $300,000 - $44,000 = $254,000? 
2) Must I put every dollar from sale, using a proper 1031 exchanger of course,  toward purchase or can I put some toward down payment (finance the rest) and use remaining cash proceeds elsewhere (pay for other things)?