Warburton is looking to sign a striker and defender but admits to being frustrated by the spending power of English teams.
This summer Rangers have signed several 30-something players on free transfers while using technicalities in FIFA regulations to sign young players from English clubs for relatively small compensation fees.
But Warburton has warned that transfer fees in England will spiral further out of reach.
The former City trader said: “We know what we’re looking for but the market is really moving down south in an aggressive manner.
“I keep being asked if the bubble is about to burst, I don’t think it’s even started yet. I think we are at the start of a cycle whereby prices are going to continue to ratchet higher in a really significant manner. We are nowhere near the mid range of that cycle yet.
“So we have to find a way of countering it, because there is money being spent down south that Scottish clubs can only dream of. Instead of moaning about it, we have got to find a solution.”
Hibernian turned down a reported £1.2million offer from Peterborough last week for Jason Cummings but Scottish clubs have generally struggled to attract decent bids for players. Oxford, who brought in £4.5million from selling two players this summer, recently bought Dundee’s top goalscorer, Kane Hemmings, for £250,000 and failed with a similar bid for Motherwell’s Marvin Johnson.
But Warburton believes the implications of ongoing Far East investment in English football will be huge.
The former Brentford manager added: “League One clubs will come and bid seven figures for Scottish players.
“There are implications because the English clubs will look for value. You will find League One clubs and bottom Championship clubs coming to Scotland to take the best players.
“And then you have a problem. Because you can’t turn round and say a player who is on x grand a week and put a £5 million price tag on his head. It doesn’t compute.
“We can’t afford the best talents to leave the game in Scotland, so we need to find investment and make sure the quality of product is always improving, and then you hopefully attract sponsors and more money.”
Meanwhile, Warburton believes it is up to him to get more value out of summer signing Niko Kranjcar.
The former Tottenham midfielder had a quiet Ladbrokes Premiership debut during Saturday’s draw against Hamilton, with former Ibrox striker Stephen Thompson claiming he had “no impact on the match whatsoever”.
Warburton said: “There seems to be a lot of emphasis on Niko’s fitness. I watch a really talented, special ball player who has probably not been appropriately challenged for a fair while now, coming in and working his socks off to get his fitness levels up.
“There are one or two bodies who maybe in three or four weeks’ time will be nearer their optimum levels of fitness.
“Some things went right for Niko on Saturday but there is no emphasis on his fitness, the emphasis is on how best we can utilise a very special player.
“There are many players at the highest level who take time to adapt to their surroundings, to the food, the area, their team-mates, etc.
“I’ve been delighted with Niko and all the new guys. We do a lot of work on their character and there is no lack of that, but sometimes it takes time. But there is no doubt in Niko we have a very talented ball player.”
On the wider lessons of the game, Warburton said: “Were we at our best? No. Can we move the ball quicker? Yes, we could. Did we take our chances? No.
“Ali Crawford, great turn and great finish, all credit to him. But we then in the second half missed seven such chances.
“We have to correct it and move forward, no doubt about that, but we are getting the ball into good areas, which is important for us.”
Rangers next face Peterhead in the second round of the Betfred Cup and will be without Martyn Waghorn, who will have a scan on his injured hamstring on Tuesday.