Answer:
girl this isn't Spanish this either france or german
Hola! Mi nombre es (your name) y esta es mi tienda en España. La mesa de madera cuesta quinientos euros. Las cuatro sillas de madera cuestan un mil y veinte euros todas juntas.
Tú casa es grande.

The difference between "tú" and "usted" depends on the formality. "Tú" is used <u>when talking to friends or relatives (informal)</u> while "usted" is used <u>when talking to older people or a person of high social rank (formal)</u>.
In this case we want to write the <u>informal</u> form of "tú", so we use "tú". Also, when dealing with <u>permanent states</u>, the verb "ser" (to be) is used.