Te alcanzo

As you may know, alcanzar means reach, but it is often the right translation for afford. Here are some examples:

• No me alcanza. I can't afford it.
• ¿Te alcanza para vivir solo? Can you afford to live on your own?

Notice in the second example that the thing being afforded is not the grammatical subject of alcanzar but rather the object of para, if present. To see this more clearly, consider: No me alcanza para más libros, not *No me alcanzaron para más libros. I don't have enough money left over for more books.

However, afford the luxury is darse el lujo.

Te alcanzo

With a personal subject, alcanzar is used for catch up to someone later, not in the sense of updating each other but rather of rejoining someone who has gone on ahead while you stay temporarily behind.

• Al rato te alcanzo. You go on ahead. I won't be far behind. I'll join you in a bit.
• ¿Por qué no nos alcanzas ahorita? Why don't you join us in a bit?
• ¿Ahorita nos alcanzan? So we'll see inside? We're going in now.

Alcanzar pairs nicely with adelantar: Adelántate con él y ahorita los alcanzo. You run ahead with him and I'll join you guys in a bit. (adapted from movie dialogue)

Alcanzar súper

Here's a usage with alcanzar that I've heard a lot recently: having (or not having) enough time.

• Alcancé súper. I got to (reached) the supermarket before they closed.
• Ya no alcanzas metro. Even if you hurry, you won't get to the metro/subway before the last train leaves.
• No alcancé a bañarme. I didn't have time to shower.

Alcanzar a ver

With the senses, alcanzar includes the idea of being able to perceive something as a result of making an effort.

• No lo alcanzo a ver. I can't make it out from here. I can't read it from this distance. It's too far way to see clearly.
• Alcancé a escucharlo. I overheard it.

The alcancía is the dropbox where you deposit your fare when boarding a bus.