The Black Cats are currently five points adrift at the bottom of the Premier League table, and Poyet, appointed as Paolo Di Canio's successor in October, would like to add his own signings to the Stadium of Light squad.
However, the Uruguayan coach has confessed that sufficient funds are not likely to be at his disposal if Sunderland's form suggests that relegation is a probability, while adding that even if unlimited money were available, a struggling side would find it difficult to bring in players with the calibre to improve them.
"I would imagine so," Poyet told the Sunderland Echo. "If I look at Sunderland as a team now and then I look at them after a win on Saturday, then it's a different Sunderland.
"But if we don't move forwards, then maybe a few of them [transfer targets] will say 'well, no'.
"It's not only about money. If we had £40m and we were going to buy my mate Mr Luis Suarez. Is he going to stay at Liverpool or come here? He's a good friend, but we're not that close!"
Di Canio made 14 summer signings, six of whom featured in Sunderland's 2-1 defeat to Tottenham Hotspur last time out, and was then sacked as boss of the Wearside outfit following a player revolt.