The kingdom finished sixth in the Sevens Challenger Series over the past fortnight to secure their spot in the final World Series Qualifier later this year.
Tu'ifua only had 11 fit players and three staff during the final tournament in Montevideo whereas most of the top teams had 14-man squads as well as half a dozen officials.
"All these teams they carried the full-staff with video analysts and a medical and strength and conditioning [coach] as well but for us it's only three," he said.
"So, that's the first challenge that I have to put forward for funding applications. I mean for this weekend we only had 11 [players] from day one...so I'm quite happy we managed to play with 11 and still be able to secure our place in the top eight."
Despite failing to make a semi final appearance in South America, Tu'ifua has no doubt the kingdom can go toe to toe with any of the other teams.
"Those teams are beatable for us. On the day we need to be smart as well," he said.
"We'll have a good chance on the day. I mean we beat Hong Kong over in Hong Kong and Germany is the other one and Japan - we have played them before and we beat them.
"This is our first opportunity for a very long time and even Uruguay so there's a bit of confidence in the background but if we have the resource that we require for preparation I think that will play a big part on the result."
The postponement of the Hong Kong Sevens because of the coronavirus outbreak, which was due to stage the World Series Qualifier in April, has also complicated Tonga's upcoming plans.
The team was due to play in a tournament organised by New Zealand Rugby at the end of March as part of their final preparations for Hong Kong but Tevita Tu'ifua said that might also need to be shifted.
The kingdom is also taking part in the final Olympic sevens qualifying tournament in France in June and World Rugby said it was "currently examining all options" around hosting the final qualifying tournament while also taking into account the "ongoing situation" regarding coronavirus and an already full Olympic Sevens calendar year.