i need to know whr i can install my jbl speakers for cheap

Lol. Most generic statement of the day. Call your local shops and price it out.

the cheaper is by yourself...

__________________
Car Sound system:
HU: **New** Ural CDD
Speaker: CDT ES-620, crossover: ES-200US, Tweeter: DRT-26 (silk) et TW-24 (silk soft)
Subwoofers: 2 x CDT ES-SQ-1200
Ampli sub: Elemental Design NIne.1 (1200W rms @ 1 ohm)
Ampli Speaker: Elemental Design NIne.2x ( 200 W rms @ 4 ohm )
RCA: Monster Cable 402XLN
Insonorisation: Portes avants et coffre arrière au B-Quiet Extreme
Power: Batterie Otpima Yellow top D35
Wiring: 0 Ga wire

Everything being installed with love an passion and a old lovely Toyota Cressida 89...

Depending on the type of vehicle and size of speakers, the most logical and cheapest option would be to install them yourself. Honestly, installing a speaker in a stock location (if the speaker is the same size as stock) is simple. If installation in the stock location is not an option, call a stereo shop who does custom work. Shop around. Its difficult to answer your question when you don't state where you are, what you are installing and in what vehicle you will be installing the gear.