Build a duplex or waste of time?

[Aroldo Villarreal]

Hello all,

My parents are willing to give me a big lot in San Antonio, TX. I would like to build a duplex (I'll attach the link below to the plans I'm looking at) so that I could move tenants in there. Do you think it's a bad idea to build new even if the land is being given to me? Will lenders lend enough money to do something like that? Does anyone know how much it costs to build in San Antonio? I bought, rehabbed, and rented a house two months ago and everything so far is going great. I'm not really experienced, any advice would help! 

Here is the link to the plans I'm thinking of buying.